Some people use a rule to see how many hours a child
should sleep at night.
subtract the child's age in years from 30,
then divide the result by 2.
tim is 12 years old.
according to the formula, how many hours should he sleep for?

What is the sum of the geometric series in which a1 = 7, r = 3, and an = 1,701? hint: cap s sub n equals start fraction a sub one left parenthesis one minus r to the power of n end power right parenthesis over one minus r end fraction comma r ≠ 1, where a1 is the first term and r is the common ratio