Wilma bought 4 boxes of Crunch-A-Lot cereal. One out of every 5 boxes
has a coupon for a free box of Crunch-A-Lot. What is the probability that Wilma got
3 coupons? What is the probability that Wilma got at least 2 coupons?

Question

Eiwoh2 · Answer

What would be the first step in solving this?

Vocaloid · Answer

first calculate the probability of getting ~1~ coupon in a box
if one out of every five boxes has a coupon, then naturally it is 1/5 chance to get a coupon and 4/5 chances not

for 3 coupons: (probability of getting a coupon)*(probability of getting a coupon)*(probability of getting a coupon)*(probability of not getting a coupon) since she bought a total of 4 boxes and only got 3 coupons