Kelvin and Danny had some money. They wanted to buy a toy that cost $35. If only Kelvin paid, the ratio of his money left to Danny's money would be 2:3. If only David paid, the ratio of Kelvin's money to the money Danny had left would be 11:4.
(a) What was the ratio of Kelvin's money to Danny's money?
(b) How much money did the boys have altogether?
\(=> {x \over y -35} = {11 \over 4}\)
\({x - 35 \over y} = {2 \over 3}\)
3(x-35)=2y
=> 3x-105=2y
=> 3x-2y=105
=>4x=11(y-35)
4x=11y-385
4x-11y=-385
12x-8y=420
12x-33y=-1155
12x-8y=420
12x-33y=-1155
25y=1575
=> y = 1575/25
=> y = 63
=> 3x-2y=105
3x-2(63)=105
3x=105+126
3x=231
x=231/3
x=77
a) Ratio of Kelvin's money to Danny's money
= 77/63 = 11/9 = 11:9
b) Boys have together $(x+y)
= $(77+63)
= $140
