The answer to this is C. Although the initial ratio of Grade 7 to Grade 8 students is 17:34, which is 1:2, and which can be represented well by the 6 sides of the cube by putting 1 and 2 as Grade 7 and 3-6 as Grade 8, the problem with the cube rolls is that the probabilities will not change after students are chosen. The problem states that students cannot be selected more than once, so the cube roll will only work the first time, and may not be accurate for subsequent rolls.
Year 1 $12500 x .07 = $875 12500-875=11625 Year 2 11625 x .07 = $813.75 11625-813.75=10811 Year 3 10811 x .07 = $756.79 10811-756.79= 10054.21 Year 4 10054.21 x .07= 703.79 10054.21-703.79= 9350.42 So after 4 years expect to get $9350.42
