Your father wants you to help him build a shed in the backyard. He says he will pay you $10 for the first week and add an additional $10.50 each week thereafter. The project will take 5 weeks. How much money will you earn, in total, if you work for the 5 weeks? I got -0.5 + 10.5n(5) = 52 but apparently its wrong. I don t know how. Im supposed to be using the arithmetic sequence formula.

So the equation for arithmetic sequences is f(n)= d(n-1)+f(1)
d being the common difference and f(1) being the first term
for this problem, the equation would be f(n)=10.5(n-1)+10

then to find the first 5 weeks you would plug in 5 for 'n' that is on the right side of the equal sign and solve using PEMDAS