PreCalculuscheck answers
posted by Lucy on .
How many ways can 5 students be chosen from a group of 4 juniors and 6 seniors to be on the prom committee if exactly 3 students must be seniors?
Answer: 5400
Find the probability of getting a sum of 5 on the first toss of two number cubes and a sum of 6 on the second toss.
Answer: 1/54
Solve e^sqrtx=4
Answer: x=1.92
Thanks

1. the 3 seniors can be chosen i C(6,3) ways, which is 20
that leaves 2 juniors to be choses from the 4 juniors, which is 6
so the number of ways is 20x6 or 120 ways
2. there are 4 ways to get a 5, (1,4),(2,3),(3,2), and (4,1)
so prob of a 5 = 4/36 = 1/9
similarly there are 5 ways to get a 6.
so the prob of a 5 followed by a 6
= 1/9 x 5/36 = 5/324
3. correct 
75*32

2300