The number of senior citizens (65 and older) in the US in millions n years after 1990 can be estimated using the formula
s=0.38n+31.2
The percentage of senior citizens living below the poverty level n years after 1990 can be estimated using the formula
p= -0.25n+12.2
a) How many senior citizens were there in 2000?
b) In what year will the percentage of seniors living below the poverty level reach 7%
c) What is the first year in which we can expect both the number of seniors to be greater than 40 million and fewer than 7% living below the poverty level?