David wants to buy some erasers and pencils with a sum of money.

If he buys 8 erasers and 6 pencils, he will have $3.50 left. If he buys 28 erasers and no pencils, he will have no money left. Each pencil costs $1.25. How much money does David have?

1 answer

Let X be the amount of money David starts with.
8 erasers + 6 pencils = X - 3.50
28 erasers = 0.
Each pencil costs $1.25, so 6 pencils at 1.25 each cost 1.25 * 6 = $<<6*1.25=7.50>>7.50
Thus, David has X - 3.50 = 7.50 dollars
David had X = 7.50 + 3.50 = $<<7.5+3.5=11>>11. Answer: \boxed{11}.