Ronda “Rowdy” Rousey

Seconds to victory:16, 66, 658, 289, 54, 267, 39, 25, 49, 25

1. n2.

∑x

3. x

4. median5. mode6. range

C-N Math 201 - Massey

Walking

Forty mothers were asked in whichmonth their child began to walk:9, 9, 10, 10, 10, 11, 11, 11, 11, 11,12, 12, 12, 12, 12, 12, 12, 12, 12, 13,13, 13, 13, 13, 13, 13, 13, 14, 14, 14,14, 14, 14, 14, 15, 15, 15, 16, 16, 17

1. Complete a table with frequency, relativefreq, and cumulative freq.

2. Mode3. Median4. Sketch a histogram.

C-N Math 201 - Massey

Have Another

Complete the table, and find the(a) mean, (b) median, and (c) mode.

x freq PDF CDF0 .4441 .4442 .7503 .9444 1

36

C-N Math 201 - Massey

High School GPA

Here is the 5 number summaryfor CN entering freshmenHS GPA’s (capped at 4)

1.87, 3.16, 3.62, 3.93, 4.00

1. Median2. Q3

3. Range4. IQR

5. Sketch boxplot6. Shape7. Bigger: mean or

median?

C-N Math 201 - Massey

January Lows1. sample size2. mean3. median4. mode5. 5 # sum.

6. shape7. range8. IQR9. 10th percentile10. % at least 32

C-N Math 201 - Massey

White as SnowEight years of annual snowfall totals(in inches) for [Whitesboro, NY]:

61, 65, 69, 83, 89, 99, 118, 125

1. mean2. median3. standard deviation4. variance5. z-score for 61

C-N Math 201 - Massey

Wimbledon 2017

Here are the seeded womens’set score results duringthe first two rounds.(e.g. winning 2-1 means X = 2− 1 = 1)

1. sample size2. complete table3. mode4. median

X freq PDF CDF−2 7 .123 .123−1 10 .1750 0 01 112 29 1

n 1C-N Math 201 - Massey

ReadingSample of Kindle customers,how may books bought last year:

x CDF... ...4 .385 .46... ...8 .699 .7610 .82... ...

1. 75th percentile2. P(X = 5)3. P(X 6= 5)4. P(X ≤ 5)5. P(X > 5)6. P(X less than 10)7. P(X at least 5)8. P(5 ≤ X ≤ 10)

C-N Math 201 - Massey

Hacking Hillary

A prognosticator believesthese probabilities for Clinton’sresults in two swing states:

outcome electoral votes probabilityboth NC and OH 33 41%NC, but not OH 15 20%OH, but not NC 18 16%

neither NC nor OH 0 23%

Find the expected number of electoral votes.

C-N Math 201 - Massey

StreakingLet the random variable X be thelongest “streak” for either side.e.g. HTHH → 2.

x P(x )1 2/16234 2/16

Finish the table and find theexpected value of X .

Ω =

HHHH,HHHT,HHTH,HHTT,HTHH,HTHT,HTTH,HTTT,THHH,THHT,THTH,THTT,TTHH,TTHT,TTTH,TTTT

C-N Math 201 - Massey

Eventually

At a carnival game, you have a5% chance of winning the bigprize on each throw.Assuming independence, find the probability of1. failing on each of your first 4 throws.2. failing on each of your first 10 throws.3. at least one success in your first 10 throws.4. How many attempts do you need so that

your probability of at least one success isgreater than 50% ?

C-N Math 201 - Massey

Current EventsProbabilities from prediction markets:I A: Alabama wins CFP 0.27I B: Biden president 0.12I C: Chicago has white Christmas 0.56

Find these joint probabilities:1. P(both A and C )

2. P(neither A nor C )

3. P(A or C )

4. P(A and B and C )

5. P(A or B or C ), i.e. at least one

C-N Math 201 - Massey

Cornea

Adult human cornea thicknessis distributed N (552, 37) microns.

1. Find the 70th percentile.2. A good LASIK candidate has at least 500

microns of corneal thickness. Whatproportion of people satisfy this condition?

3. Out of 300 people interested in LASIK,approximately how many will have corneasthat are too thin ?

C-N Math 201 - Massey

Ten O’clock ScholarEach (x , y) point represents one U.S. state.

1. Find theslope.

2. Find thecorrelation.

3. Tennessee hasx = 17.5. Find y .

C-N Math 201 - Massey

Secret Shopper

In a sample of 236 orders at fast food franchises,17.8 percent experienced at least one problemand were not filled correctly.1. How many orders were not filled correctly.2. Write the 95% CI for p as

“point estimate” ± MOE.

C-N Math 201 - Massey

Sibling Gap

A sample of n = 50 1st-2nd childsibling pairs revealed that themean age gap was x = 34 months,with s = 19 months.Consider confidence intervals forµ, the population mean.Find the margin of error for:1. 90% confidence2. 95% confidence3. 99% confidence

C-N Math 201 - Massey

Fill ’er UpThe Bureau of Weights and Measuresperiodically tests gas pump accuracy.Suppose the inspector pumps 5 “gallons” thatshould be 128 ounces each. Instead, he observedan average of x = 126 oz with s = 1.6 oz.Using H.T. notation, state:1. the null hyp.2. the 2-tailed alt hyp.3. the discrepancy x − µ04. the p-value5. your conclusion if α = .05.

C-N Math 201 - Massey

Statistical Tie

Two brothers spend the day [skeet] shooting.I Austin: hit 72% of 125 shotsI Billy: hit 65% of 200 shots

Momma asks who done better andAustin claims victory. But Billyasks for a formal test of the significance.1. null hypothesis2. p-value for two-tailed test3. Is the 7 percentage point difference

in the brothers’ performancesstatistically significant ?

C-N Math 201 - Massey

Infused

Scalp moisture (scale 0− 100)was measured for a treatment(almond oil) and control groups.

n x streatment 3000 75.8 9.4control 7000 75.1 9.1

1. Find the p-value forH1 : µT > µC .

2. With α = .01, is the differencein scalp moisturestatistically significant ?

C-N Math 201 - Massey