Ernest wants to buy 21 new books for his book collection. If the average price for a book is $20.45, about how much should he plan to spend?

If each book cost $20.45 then you times it by 21 and the answer you would get is 429.45

Step-by-step explanation:

im 99% that its correct

He should expect to spend as much as 429.45 (to be exact)

Step-by-step explanation:

It's really just simple math $20.45 multiplied by 21 is 429.45 (:

I'm sorry if I'm wrong. Have a great day and good luck!

im here

step-by-step explanation:

85.560%

step-by-step explanation:

conditional probability is defined as:

p(a|b) = p(a∩b) / p(b)

in other words, the probability that a occurs, given that b has occurred = the probability that both a and b occur / the probability that b occurs.

in this example:

p(turns 64 | turns 44) = p(turns 64 & turns 44) / p(turns 44).

if someone turns 64, they must have already turned 44, so:

p(turns 64 | turns 44) = p(turns 64) / p(turns 44)

on page 42, we see that of the original 100,000, 94944 turn 44, and 81234 turn 64.   therefore:

p(turns 64 | turns 44) = 81234 / 94944

p(turns 64 | turns 44) = 0.85560