Let x = the number of mushrooms she gathered in the first hour. Then the number of mushrooms she gathered in the second hour is (x+7), and the number of mushrooms she gathered in the third hour is (x+6). x + (x + 7) + (x + 6 ) = 37 3x + 13 = 37 3x = 37 - 13 = 24 ====> x == 8. From this point, complete the solution on your own.