Billy, Michael, Oscar and Ahmad paid a total of $252 for a present. Ahmad paid ¹₂ of what the rest paid. Billy paid 40% of what the rest paid. Michael and Oscar paid an equal amount of money. How much did Oscar pay?

Billy	Michael	Oscar	Ahmad	Total
2x7			1x7	3x7
2x3	5x3			7x3
	1	1
6 u	4 u	4 u	7 u	21 u

40%= ⁴⁰₁₀₀= ²₅
Billy's share : Total share = 2 : 5

The total amount paid for the present is repeated.  Make the total amount the same.  LCM of 3 and 7 is 21.

Amount that Michael, Oscar and Ahmad paid = 15 u

Amount that Michael and Oscar paid
= 15 u - 7 u
= 8 u

The amount that Michael and Oscar each paid is the same.

Amount that Michael and Oscar each paid
= 8 u ÷ 2
= 4 u

Cost of the present = 21 u

21 u = 252

1 u = 252 ÷ 21 = 12

Amount that Oscar paid
= 4 u
= 4 x 12
= $48

Answer(s): $48