Hugo received $100 for his birthday. he
then saved $20 per week until he had
a total of $460 to buy a printer. use an
equation to show how many weeks it took
him to save the money.

18 weeks

Step-by-step explanation:

Total amount of money saved up to buy the printer is T(w), where w is the number of weeks.

Then T(w) = $100 + ($20/wk)w

Setting this equal to $460, we solve the resulting equation for w to determine the number of weeks it took Hugo to save up $460 total:

$460 = $100 + ($20/wk)w, or

$360 = ($20/wk)w, or

w = $360/($20/wk) = 18 weeks

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