Embed Size (px)
Citation preview
Do Now 10/13/09Do Now 10/13/09Take out HW from last night.Take out HW from last night.
– Text p. 165, #28-34 even, #46-50 even
– Text p. 171-172, #16-38 even
Copy HW in your planner.Copy HW in your planner.
– Text p. 179-181 #4-36 evenText p. 179-181 #4-36 even
If you are shopping in the mall and see that a shirt is on sale for 40% If you are shopping in the mall and see that a shirt is on sale for 40% off, what does that mean? If the price of the shirt is $30 how much will off, what does that mean? If the price of the shirt is $30 how much will it cost you to purchase it?it cost you to purchase it?
HomeworkHomework Text p. 165, #28-34 even, #46-50 evenText p. 165, #28-34 even, #46-50 even28) 4/12 = n/3; n = 1
30) t/21 = 40/28; t = 30
32) 3.3
34) 2
46) 7/8
48) 3/5
50) 21 pages
HomeworkHomework Text p. 171-172, #16-38 EVENText p. 171-172, #16-38 EVEN
16) D18) Distribute the 14 to both b and 2; 18b = 14b + 28, 4b = 28, b = 720) 222) 2224) -2.526) 5.228) 7.430) -7.132) Decreases; as k gets larger, the value of (k/14) get larger. Therefore h must get smaller so that (5/h) will get larger.34) 18 min36) 48 km38) 70.5 km
Objective
SWBAT solve percent problems
Percent-Percent- means ‘per one hundred’ or means ‘per one hundred’ or
divided by 100. divided by 100. How many cents are there in a dollar?
Percent Problems Using Percent Problems Using Proportions-Proportions-
You can represent You can represent “a“a is is pp percent of percent of bb” ” using the proportionusing the proportion
100
p
b
a
where where a a is a part of the base is a part of the base b b and , or and , or pp%, %, is the percent.is the percent.
100
p
Try It Out…Try It Out…
p68
What percent of 25 is 17?What percent of 25 is 17?Write a proportion where Write a proportion where 2525 is the is the base and base and 1717 is a part of the base. is a part of the base.
100
p
b
a
10025
17 p
Percent proportionPercent proportion
Substitute and Substitute and then cross multiplythen cross multiply
p251700
17 is 68% of 2517 is 68% of 25
Try It Out…Try It Out…
p5.37
What percent of 136 is 51?What percent of 136 is 51?Write a proportion where Write a proportion where 136136 is the is the base and base and 5151 is a part of the base. is a part of the base.
100
p
b
a
100136
51 p
Percent proportionPercent proportion
Substitute and Substitute and then cross multiplythen cross multiply
p1365100
51 is 37.5% of 13651 is 37.5% of 136
Percent Problems Using Equations-Percent Problems Using Equations-
You can represent You can represent “a“a is is pp percent of percent of bb” ” using the equationusing the equation
bpa %
where where a a is a part of the base is a part of the base b b and and p%, p%, is is the percent.the percent.
Try It Out…Try It Out…
2.13a
What number is 15% of 88?What number is 15% of 88?Use an equation where Use an equation where 15%15% is the is the percent and percent and 8888 is the base. is the base.
bpa %
88%15 a
Percent equationPercent equation
Substitute and Substitute and then solve the equationthen solve the equation 8815.0 a
13.2 is 15% of 8813.2 is 15% of 88
Try It Out…Try It Out…
b160
20 is 12.5% of what number?20 is 12.5% of what number?Use an equation where Use an equation where 12.5%12.5% is the is the percent and percent and 2020 is a part of the base. is a part of the base.
bpa %
b %5.1220
Percent equationPercent equation
Substitute and Substitute and then solve the equationthen solve the equation
b 125.020
20 is 12.5% of 16020 is 12.5% of 160
What Have We Learned… What Have We Learned…
Types of Percent ProblemsTypes of Percent Problems
(1) Find a percent(1) Find a percent What percent of 136 is 51?What percent of 136 is 51?
(2) Find a part of a base(2) Find a part of a base What number is 15% of 88?What number is 15% of 88?
(3) Find a base(3) Find a base 20 is 12.5% of what number? 20 is 12.5% of what number?
What Happens When Cupid Shoots What Happens When Cupid Shoots an Arrow?an Arrow?
He Mrs. SomeoneHe Mrs. Someone
HomeworkHomeworkText p. 179-181 #4-36 evenText p. 179-181 #4-36 even
