A bag contains $510 in the form of 50 p, 25 p and 20 p coins in the ratio 2 : 3 : 4. Find the number of coins of each type.
Choose the correct choice from the following answers: A) 200, 400, 500 B) 300, 200, 600 C) 800, 400, 600 D) 400, 600, 800 E) 600, 700, 900
Let the number of 50 p, 25 p and 20 p coins be 2x, 3x and 4x.   Then 2x × 50/100 + 3x × 25/100 + 4x × 20/100 = 510   x/1 + 3x/4 + 4x/5 = 510   (20x + 15x + 16x)/20 = 510   ⇒ 51x/20 = 510   x = (510 × 20)/51   x = 200   2x = 2 × 200 = 400   3x = 3 × 200 = 600   4x = 4 × 200 = 800.   Therefore, number of 50 p coins, 25 p coins and 20 p coins are 400, 600, 800 respectively.   Answer is 400, 600, 800
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A bag contains $510 in the form of 50 p, 25 p and 20 p coins in the ratio 2 : 3 : 4. Find the number of coins of each type.