Lenny wants to buy a lawn mower priced at $266, if he pays cash. He can buy it on credit for $288. The reason he pays more on credit is because he also has to pay interest.

If Lenny buys the mower on credit, how much will he pay in interest?

x equals 1

step-by-step explanation:

f(4)=f(×)

x=1

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