CPM Homework Help : A2C Problem 11-74

Hint (a-i):

Add (or subtract) the same amount again.

Answer (a-ii):

t(n) = 36 − 12n

Hint (a-iii):

Try graphing the sequence as a function.

Hint (a-iv):

Substitute −624 for t(n) and solve for n.

Hint (b-i):

Multiply (or divide) by the same amount again.

Answer (b-ii):

$t(n)=48\left(\frac{1}{2}\right)^{n}$

Hint (b-iii):

Try graphing the sequence as a function.

Hint (b-iv):

$\text{Substitute }\frac{3}{128}\text{ for } t(n)\, \text{and solve for n.}$