Use the equation 300⇒5x to find how much tim made each day on average. x⇒60 so, Day 1: $60, Day 2: $70 etc.. so the equation 300=5x+10 suffices the problem. 300⇒5x+10 ⇒ 290=5x x=58 So, Tim earned $58 his first day. Hope this helped.
The given problem is based on arithmetic sequence Sn = 300 (the sum of money in five days) d = 10 (the difference day by day) n = 5 The question asks how much Tim earn on the first day, we write it as a₁
The general formula to find the sum of a sequence is n/2 (2a₁ + d(n-1)) = Sn
Input the numbers to the formula to find the value of a₁ n/2 (2a₁ + d(n-1)) = Sn 5/2 (2a₁ + 10(5-1)) = 300 5/2 (2a₁ + 10(4)) = 300 5/2 (2a₁ + 40) = 300 2a₁ + 40 = 300 × 2/5 2a₁ + 40 = 120 2a₁ = 120 - 40 2a₁ = 80 a₁ = 80/2 a₁ = 40
