a contractor pays $150 penalty for the first extra day she takes to complete a job. The daily charge is increased $60 each day thereafter. What is the penalty on day 5?

Answer 1

150+60(5-1) = 150+240 = $390 penalty on day 5

it's an arithmetic sequence, common difference = 60, 1st term =150

an = a1 +d(n-1) = nth term

a5 = 150+60(5-1) = 390