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Copyright MATHCOUNTS, Inc. 2015. All rights reserved. Name DO NOT BEGIN UNTIL YOU ARE INSTRUCTED TO DO SO. This section of the competition consists of 30 problems. You will have 40 minutes to complete all the problems. You are not allowed to use calculators, books or other aids during this round. Calculations may be done on scratch paper. All answers must be complete, legible and simplified to lowest terms. Record only final answers in the blanks in the left-hand column of the competition booklet. If you complete the problems before time is called, use the remaining time to check your answers. In each written round of the competition, the required unit for the answer is included in the answer blank. The plural form of the unit is always used, even if the answer appears to require the singular form of the unit. The unit provided in the answer blank is the only form of the answer that will be accepted. Total Correct Scorer’s Initials FOUNDING SPONSORS: National Society of Professional Engineers, National Council of Teachers of Mathematics and CNA Foundation 2016 School Competition Sprint Round Problems 130 0 1 2 3 4 5 6 7 8 9 NATIONAL SPONSORS Raytheon Company Northrop Grumman Foundation U.S. Department of Defense National Society of Professional Engineers CNA Foundation Phillips 66 Texas Instruments Incorporated 3Mgives Art of Problem Solving NextThought

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Page 1: 2016 School Competition 5 Sprint Round Problems …gammonmathematics.weebly.com/uploads/2/2/9/1/22919132/...According to this order form for Tessa’s art supplies, the total cost

Copyright MATHCOUNTS, Inc. 2015. All rights reserved.

Name

DO NOT BEGIN UNTIL YOU ARE INSTRUCTED TO DO SO.

This section of the competition consists of 30 problems. You will have 40 minutes to complete all the problems. You are not allowed to use calculators, books or other aids during this round. Calculations may be done on scratch paper. All answers must be complete, legible and simplified to lowest terms. Record only final answers in the blanks in the left-hand column of the competition booklet. If you complete the problems before time is called, use the remaining time to check your answers.

In each written round of the competition, the required unit for the answer is included in the answer blank. The plural form of the unit is always used, even if the answer appears to require the singular form of the unit. The unit provided in the answer blank is the only form of the answer that will be accepted.

Total Correct Scorer’s Initials

Founding SponSorS: National Society of Professional Engineers, National Council of Teachers of Mathematics and CNA Foundation

2016School Competition

Sprint RoundProblems 1−30

0

1

2

3

4

5

6

7

8

9

NatioNal SpoNSorS

Raytheon Company Northrop Grumman Foundation

U.S. Department of DefenseNational Society of Professional Engineers

CNA FoundationPhillips 66

Texas Instruments Incorporated 3Mgives

Art of Problem SolvingNextThought

Page 2: 2016 School Competition 5 Sprint Round Problems …gammonmathematics.weebly.com/uploads/2/2/9/1/22919132/...According to this order form for Tessa’s art supplies, the total cost

Copyright MATHCOUNTS, Inc. 2015. All rights reserved. 2016 School Sprint Round

1. _____________

2. _____________

3. _____________

4. _____________

5. _____________

6. _____________

What is the temperature according to this thermometer that measures temperature in degrees Celsius?

Cory has a summer job at the local grocery store. How much will Cory get paid to work 20 hours each week for 8 weeks if he earns $10 an hour?

What is the value of 21 divided by 78 ?

T������� E���������

40

20

16 – 206 – 10

Teachers

Years

50

30

10

11 – 151 – 5

The graph shows the results when 100 teachers reported the number of years they have been teaching. What percent of these teachers have been teaching more than 5 years but no more than 15 years?

Let a ☺ b = 2a − 3b. What is the value of (1 ☺ 2) ☺ 7?

If 8

14 =4d , what is the value of d ?

°C

2

4

6

8

10

12

$

percent

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Copyright MATHCOUNTS, Inc. 2015. All rights reserved. 2016 School Sprint Round

7. _____________

8. _____________

9. _____________

10. _____________

11. _____________

12. _____________

The figure shows the first four stages of a dot pattern. If the pattern continues, how many dots will be in the figure for Stage 7?

According to this order form for Tessa’s art supplies, the total cost for the 20 items she ordered was $150.00. Some of the details of Tessa’s order are missing from the order form, but based on the information given, what was the unit price for each sketch pad Tessa ordered?

A length of 240 feet of fencing is to be supported by a total of 13 evenly spaced fence posts, including one at each end, as shown. How far apart must the fence posts be spaced?

This coordinate grid shows pentagon ABCDE with vertices A(3, 0), B(4, 0), C(4, 7), D(0, 7) and E(0, 5). What is its area? Express your answer as a decimal to the nearest tenth.

Maria baked a batch of cookies. She ate three cookies and then 45 of the cookies

were left. How many cookies did Maria bake?

If + = + + and = 16 – + ( ), what is the value of +  ?

dots

Stage 1 Stage 2 Stage 3 Stage 4

$

ORDER FORMI��� Q������� U��� P���� T��� C��Paint BrushAcrylic Paint

Sketch Pad

10

4

$ 8.00 $ 48.00

$ 75.00

20 $150.00$

$

$

feet

x

y

A B

D C

Eunits2

cookies

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Copyright MATHCOUNTS, Inc. 2015. All rights reserved. 2016 School Sprint Round

13. _____________

14. _____________

15. _____________

16. _____________

17. _____________

18. _____________

The weights of four students on a wrestling team are 100 pounds, 108 pounds, 113 pounds, and 119 pounds. What is the mean weight of the four students?

A 5-foot ribbon is cut into two pieces with lengths in the ratio 1:4. How many inches long is the shortest piece?

While jogging, Cher’s heart pumped 450 gallons of blood in 1 hour, 15 minutes. On average, how many gallons of blood did her heart pump each minute?

What are the coordinates of the image of P, when this figure is reflected across the y-axis? Express your answer as an ordered pair.

The glee club had a fund-raiser selling cookies to raise money for a spring concert. The club kept half of the money collected from selling cookies for $5 per box. How many boxes of cookies were sold if the glee club kept $1250?

The length of a rectangle is twice its width. The rectangle has an area of 128 cm2. What is its perimeter?

pounds

inches

5 feet

gallons

P

x

y

2 4−4 −2

2

4

6

8

( , )

boxes

cm

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Copyright MATHCOUNTS, Inc. 2015. All rights reserved. 2016 School Sprint Round

19. _____________

20. _____________

21. _____________

22. _____________

23. _____________

24. _____________

How many two-digit positive integers less than 25 have the property that they are divisible by each of their digits?

The three-digit integer 5A4 is a multiple of six. What is the sum of all the possible values for the digit represented by A?

The total cost of Keegan’s lunch was $4.56. He paid with a 5-dollar bill and received exact change. What is the fewest number of coins Keegan could have received?

The line passing through (−3, 2) and (7, −1) intersects the x-axis at the point (a, 0). What is the value of a? Express your answer as a common fraction.

The prize money in a science fair is divided among the top three winners so that the amount awarded for first place is four times the amount for third place, and the amount for second place is three times the amount for third place. If the total amount of prize money is $2400, what is the amount awarded for second place?

In right triangle ABC, shown here, mA = 40°, and D is on side AC such that segment BD bisects CBA. What is the degree

measure of BDC?

integers

coins

$

A

B

C D

40˚

degrees

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Copyright MATHCOUNTS, Inc. 2015. All rights reserved. 2016 School Sprint Round

25. _____________

26. _____________

27. _____________

28. _____________

29. _____________

30. _____________

Addie’s one-quart fruit salad is strawberries and blueberries. Ashlyn’s

one-quart fruit salad is strawberries and blueberries. When Addie and

Ashlyn combine their fruit salads, what portion of the mixture is strawberries?

Express your answer as a common fraction.

How many triangles are in the figure shown here?

J.R.R. Tolkien, author of The Hobbit, stated in 1970 that on one of his birthdays the age he turned was the square root of the year. In what year was he born?

Twins Cara and Dara drove from their house to the beach in exactly 5 hours, not including rest stops. First, Cara drove at an average speed of 40 mi/h and stopped at a rest area located halfway between their house and the beach. Then Dara drove from that location to the beach at an average speed of 60 mi/h. For how many hours did Dara drive?

For the rectangular solid shown, AB = 12 units, BC = 8 units and AE = 6 units. What is the volume of the tetrahedron DHBC?

Bobby attends an event along with two friends. At the event, there is a drawing for three door prizes. Each person in attendance has an equal chance of winning a prize and no one can win more than one prize. If there are 20 people at the event, including Bobby and his two friends, what is the probability that Bobby and both of his friends each will win a prize? Express your answer as a common fraction.

14

341

212

triangles

hours

A B

CD

E F

GH

units3

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Copyright MATHCOUNTS, Inc. 2015. All rights reserved.

Name

DO NOT BEGIN UNTIL YOU ARE INSTRUCTED TO DO SO.

This section of the competition consists of eight problems, which will be presented in pairs. Work on one pair of problems will be completed and answers will be collected before the next pair is distributed. The time limit for each pair of problems is six minutes. The first pair of problems is on the other side of this sheet. When told to do so, turn the page over and begin working. This round assumes the use of calculators, and calculations also may be done on scratch paper, but no other aids are allowed. All answers must be complete, legible and simplified to lowest terms. Record only final answers in the blanks in the left-hand column of the problem sheets. If you complete the problems before time is called, use the time remaining to check your answers.

Founding SponSorS: National Society of Professional Engineers, National Council of Teachers of Mathematics and CNA Foundation

2016School Competition

Target RoundProblems 1 & 2

NatioNal SpoNSorS

Raytheon Company Northrop Grumman Foundation

U.S. Department of DefenseNational Society of Professional Engineers

CNA FoundationPhillips 66

Texas Instruments Incorporated 3Mgives

Art of Problem SolvingNextThought

Scorer’s InitialsProblem 1 Problem 2

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Copyright MATHCOUNTS, Inc. 2015. All rights reserved. 2016 School Target Round

2. _______________

Kelly has $12.00 in dimes and quarters. She has six more quarters than dimes. How many dimes does Kelly have?

dimes

The height of a bean plant is measured daily. At the end of the second day of

observations, it measured 1 inch in height. Thereafter, its height doubled every

two days. At the end of which day will the plant measure exactly 16 inches tall?

day

1. _______________

Page 9: 2016 School Competition 5 Sprint Round Problems …gammonmathematics.weebly.com/uploads/2/2/9/1/22919132/...According to this order form for Tessa’s art supplies, the total cost

Copyright MATHCOUNTS, Inc. 2015. All rights reserved.

Name

DO NOT BEGIN UNTIL YOU ARE INSTRUCTED TO DO SO.

Founding SponSorS: National Society of Professional Engineers, National Council of Teachers of Mathematics and CNA Foundation

2016School Competition

Target RoundProblems 3 & 4

NatioNal SpoNSorS

Raytheon Company Northrop Grumman Foundation

U.S. Department of DefenseNational Society of Professional Engineers

CNA FoundationPhillips 66

Texas Instruments Incorporated 3Mgives

Art of Problem SolvingNextThought

Scorer’s InitialsProblem 3 Problem 4

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Copyright MATHCOUNTS, Inc. 2015. All rights reserved. 2016 School Target Round

3. _____________

4. _____________

Koda teaches a total of 25 students in three different swimming classes. He teaches his first two classes on Friday and his third class on Saturday. There are seven students in Koda’s Saturday class. What is the average number of students in Koda’s Friday classes?

students

What is the least positive integer n such that the product of 2016 and n ends in the digits 00?

Page 11: 2016 School Competition 5 Sprint Round Problems …gammonmathematics.weebly.com/uploads/2/2/9/1/22919132/...According to this order form for Tessa’s art supplies, the total cost

Copyright MATHCOUNTS, Inc. 2015. All rights reserved.

Name

DO NOT BEGIN UNTIL YOU ARE INSTRUCTED TO DO SO.

Founding SponSorS: National Society of Professional Engineers, National Council of Teachers of Mathematics and CNA Foundation

2016School Competition

Target RoundProblems 5 & 6

NatioNal SpoNSorS

Raytheon Company Northrop Grumman Foundation

U.S. Department of DefenseNational Society of Professional Engineers

CNA FoundationPhillips 66

Texas Instruments Incorporated 3Mgives

Art of Problem SolvingNextThought

Scorer’s InitialsProblem 5 Problem 6

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Copyright MATHCOUNTS, Inc. 2015. All rights reserved. 2016 School Target Round

5. _____________

6. _____________

A cubic yard of sand is spread uniformly to completely cover a rectangular path that is 3 feet wide and 24 feet long. How many inches deep is the sand that covers this path? Express your answer as a mixed number.

inches

In the figure shown, how many paths are there that move only upward from A to B?

A

Bpaths

Page 13: 2016 School Competition 5 Sprint Round Problems …gammonmathematics.weebly.com/uploads/2/2/9/1/22919132/...According to this order form for Tessa’s art supplies, the total cost

Copyright MATHCOUNTS, Inc. 2015. All rights reserved.

Name

DO NOT BEGIN UNTIL YOU ARE INSTRUCTED TO DO SO.

Founding SponSorS: National Society of Professional Engineers, National Council of Teachers of Mathematics and CNA Foundation

2016School Competition

Target RoundProblems 7 & 8

NatioNal SpoNSorS

Raytheon Company Northrop Grumman Foundation

U.S. Department of DefenseNational Society of Professional Engineers

CNA FoundationPhillips 66

Texas Instruments Incorporated 3Mgives

Art of Problem SolvingNextThought

Scorer’s InitialsProblem 7 Problem 8

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Copyright MATHCOUNTS, Inc. 2015. All rights reserved. 2016 School Target Round

7. _____________

8. _____________

With a $20 bill, Britt can buy 40 pencils, or 25 erasers, or 80 bookmarks, with no change left over. If Britt wants to use $20 to make sets consisting of one pencil, one eraser, and one bookmark each, how many complete sets can he buy?

sets

A piece of wire measuring 48 feet long is cut into two pieces of equal length. One piece is bent into an equilateral triangle and the other is bent into a circle. What is the combined area of the two shapes? Express your answer to the nearest whole number.

ft2

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Copyright MATHCOUNTS, Inc. 2015. All rights reserved.

Total Correct Scorer’s Initials

Founding SponSorS: National Society of Professional Engineers, National Council of Teachers of Mathematics and CNA Foundation

2016School Competition

Team RoundProblems 1−10

TeamMembers , Captain

NatioNal SpoNSorS

Raytheon Company Northrop Grumman Foundation

U.S. Department of DefenseNational Society of Professional Engineers

CNA FoundationPhillips 66

Texas Instruments Incorporated 3Mgives

Art of Problem SolvingNextThought

DO NOT BEGIN UNTIL YOU ARE INSTRUCTED TO DO SO.

This section of the competition consists of 10 problems which the team has 20 minutes to complete. Team members may work together in any way to solve the problems. Team members may talk to each other during this section of the competition. This round assumes the use of calculators, and calculations also may be done on scratch paper, but no other aids are allowed. All answers must be complete, legible and simplified to lowest terms. The team captain must record the team’s official answers on his/her own competition booklet, which is the only booklet that will be scored. If the team completes the problems before time is called, use the remaining time to check your answers.

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Copyright MATHCOUNTS, Inc. 2015. All rights reserved. 2016 School Team Round

1. _____________

2. _____________

3. _____________

4. _____________

5. _____________

A particular coin that is composed only of silver and copper has a mass of

5 grams. If copper accounts for 9

10 of the coin’s mass, what is the mass of the

silver in the coin? Express your answer as a decimal to the nearest tenth.

How many ordered pairs of integers (a, b) satisfy a × b = 60?

The final bill for the Freeman’s dinner, including a 20% tip, was $72. What was the total cost of the Freeman’s dinner before the tip was added?

Tucker has a jar containing 4 green and 5 blue marbles. What is the minimum number of marbles Tucker needs to remove from the jar, without replacement, to guarantee that he has at least four marbles of the same color among those removed?

A rectangular piece of paper measures 8 inches by 4 inches. The paper is folded along a crease from the upper left corner to a point located 3 inches from the lower left corner along the bottom edge, creating a right triangle as shown. What is the area of the shaded region?

grams

orderedpairs

$

marbles

3

8

4

in2

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Copyright MATHCOUNTS, Inc. 2015. All rights reserved. 2016 School Team Round

The product of three consecutive prime numbers is 105. What is their sum?

Everett’s batting average is 0.300 after getting 120 hits in 400 times at bat. How many hits must he get in his next 100 times at bat to raise his average to 0.400?

The lines given by the equations y = x + 1 and y = ax + b are perpendicular and intersect at the point (2, 3). What is the value of a + b?

The Farmington family has two different silos on their farm. The first silo is a circular cylinder of height 20 ft with parallel bases of diameter 14 ft. The second silo is a cylinder of height 22 ft topped by a cone of height 10 ft, both with bases of diameter 12 ft. What is the absolute difference between the volumes of the two silos? Express your answer in terms of π.

Regular octagon ABCDEFGH with side length 2 units is placed on a coordinate plane such that side AB lies on the positive y-axis and side CD lies on the positive x-axis. What is the absolute difference between the x- and y-coordinates of F? Express your answer in simplest radical form.

hits

ft3

6. _____________

7. _____________

8. _____________

9. _____________

10. _____________