Question

Linda saved some money every month from august to December. Each month , she save $15 more than the month before. If the average amount of money she saved for the 5 months was $200 , how much did she save in august?

Answer 1

if in Aug she saves a then she saves a. a+d. a+2d. a+3d. a+4d. whose av is a+30=200 becz d=15. thus a=170

Answer 2

Let the money she saved in august be $x
According to the problem,
x+(x+15)+(x+15+15)+(x+15+15+15)+(x+15+15+15+15)=$200
or, 5x + 150= 200
or, 5x =200 - 150
or, x = 50÷5
or, x = 10
:. The money she saved in August = $x = $10