Ichiro's batting average in baseball is 0.342. This is 0.08 higher than Giancarlo's batting average. What is
Giancarlo's batting average?

question is incomplete.

the revenue of the fitness center, y, is the product of two factors: the number of members and the fee paid by each member. there are 320 members now, but number of members goes down by 10 for each $5 increase in fees, so if x is the number of $5 price increases then members is equal to (320 - 10x). since the fee is currently $45, and the fee increases by $5 for every price bump x, the fee is given by (45 + 5x). so, revenue y is given by y = (320 - 10x)(45 + 5x).

pi or 3.14159265359 is an irratinal decimal