Answer:
It's C
Step-by-step explanation:
Answer:
The mean number of adults who would have bank savings accounts is 32.
Step-by-step explanation:
For each adult surveyed, there are only two possible outcomes. Either they have bank savings accounts, or they do not. So we use the binomial probability distribution to solve this problem.
Binomial probability distribution
Probability of exactly x sucesses on n repeated trials, with p probability.
The expected value of the binomial distribution is:

In this problem, we have that:

If we were to survey 50 randomly selected adults, find the mean number of adults who would have bank savings accounts.
This is E(X) when
.
So

The mean number of adults who would have bank savings accounts is 32.
Answer:
7 Hours 12 Minutes
Step-by-step explanation:
So they one of the printer increases at a rate of 1/12 and the other increases at a rate of 1/18. Since you don't know the time it actually takes, you will replace both numerators with and x. (x/12 and x/18). You want to set these up so that they are adding. (x/12 + x/18=1). Since you're adding, you want to change it to the same denominator. The lowest is 36 so you multiply x/12 by 3/3 (so you don't unbalance the equation) and x/18 by 2/2. You'll end up with 3x/36 + 2x/36= 1 which will simplify to 5x/36=1. Multiply each side by 36 to leave the variable by itself. It becomes 5x=36 and when you divide it by 5 you get 7.2. So it's seven and .2 hours, which is equivalent to7 and 1/5 of an hour or 7 hours and 12 minutes.
Root of ( 20^2 - 16^2 ) = 12