The original price of a tractor was $55,000. The value decreases in value at a
steady rate of 11% per year. What will the tractor be worth in 8 years?
A) $21,651.24
B) $65,487.22
C) $45,591.35
D) $12,536.25

A) $21,651.24

x = p(1 - r)ⁿ

p = $55000

r = 11%  = 0.11

n = 8 years

x = $55000(1 - 0.11)⁸

= $55000ₓ0.89⁸

= $55000ₓ0.39365888057

= $21651.24

correct

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