Question

9 The ratio of the number of coins Azam had to the number of coins Eddie had was 3:7. Eddie gave 42 coins to Azam and they ended up having the same number of coins. How many coins did each person have at first?​

Answer 1

If Azam has x coins, Eddie have y coins
x:y = 3:7 (1)
y-42 = x+42 (2)
(2): y=x+84
put (2) into (1)
x:x+84 = 3:7
7x = 3x+252
4x = 252
x = 63 (3)
put (3) into (2)
y-42 = 63+42
y-42 = 105
y = 147
Adam have 63 coins at first and Eddie have 147 coins at first.