15 plus what equals 40

If f(x) = 3-2x and g(x) =1/x+5 to what is the value (f/g)(8)

With this one. will mark brainliest

The amount cami raised during last year’s charity walk, $45.50, is 7/10 of the amount she raised this year. which equation represents n, the number of dollars she raised this year?