John's salary to Peter's salary is 5 : 6. The former saves $2120 while the latter saves $2480. If Peter's spending to John's spending is in the ratio of 4 : 3, what are John's and Peter's salaries respectively?
- John
- Peter
| John's salary |
Peter's salary |
| 5 u |
6 u |
| Savings |
Spending |
Savings |
Spending |
| $2120 |
3 p |
$2480 |
4 p |
2120 + 3 p = 5 u --- (1)
2480 + 4 p = 6 u --- (2)
Make p the same.
(1)
x 48480 +
12 p = 20 u
12 p = 20 u - 8480 --- (3)
(2)
x 37440 +
12 p = 18 u
12 p = 18 u - 7440 --- (4)
(3) = (4)
20 u - 8480 = 18 u - 7440
20 u - 18 u = 8480 - 7440
2 u = 1040
1 u = 1040 ÷ 2 = 520
(a)
John's salary
= 5 u
= 5 x 520
= $2600
(b)
Peter's salary
= 6 u
= 6 x 520
= $3120
Answer(s): (a) $2600; (b) $3120
