Homework # 9 - MATH 2227
The problems on this homework must be done alone. The honor code is in effect.
First name: Last name:
(For questions 1 and 2) A burger restaurant offers a promotion. With the purchase of every meal, you get a coupon to use for your next purchase. 85\(\%\) of the coupons are worth $1, 10\(\%\) of the coupons are worth $2, 4\(\%\) of the coupons are worth $5. And 1\(\%\) of the coupons are worth $20.
1. Find the expected value, \(\mu\), of the coupon.
a. $1.45
b. $1.85
c. $2.25
d. $2.65
d. $3.05
2. Find the standard deviation, \(\sigma\), for the value of the coupon.
a. $1.80
b. $2.04
c. $3.33
d. $4.23
d. $5.94
3. If you flip a fair coin 10 times, find the probability of flipping exactly 5 heads (rounded to the nearest 1%.
a. 15%
b. 25%
c. 35%
d. 45%
d. 55%
4. Assuming that birthdays are uniformly distributed among 365 days in a year, compute the probability that in a randomly selected group of 40 people, at least two share a birthday.
a. 11.0\(\%\)
b. 29.3\(\%\)
c. 60.1\(\%\)
d. 78.8(\%\)
d. 89.1\(\%\)
(For questions 5 to 9) The chance of winning a particular game is \(\frac{1}{4}\). Say we play the game 10 times.
5. Find the chance of winning exactly two times.
a. 23.5\(\%\)
b. 25.6\(\%\)
c. 28.2\(\%\)
d. 29.8\(\%\)
d. 30.1\(\%\)
6. Find the chance of winning fewer than 3 times.
a. 52.6\(\%\)
b. 60.6\(\%\)
c. 70.4\(\%\)
d. 75.2\(\%\)
d. 77.6\(\%\)
7. Find the chance of winning at least 3 times.
a. 22.4\(\%\)
b. 24.8\(\%\)
c. 29.6\(\%\)
d. 39.4\(\%\)
d. 47.4\(\%\)
8. If r denotes the the number of wins, find the expected value, \(\mu\) for r.
a. 1
b. 1.5
c. 2
d. 2.5
d. 3
9. If r denotes the the number of wins, find the standard deviation,\(\sigma\) for r.
a. 1.20
b. 1.32
c. 1.37
d. 1.88
d. 1.95