Luis's salary to David's salary is 4 : 5. The former saves $610 while the latter saves $590. If David's spending to Luis's spending is in the ratio of 7 : 5, what are Luis's and David's salaries respectively?
- Luis
- David
| Luis's salary |
David's salary |
| 4 u |
5 u |
| Savings |
Spending |
Savings |
Spending |
| $610 |
5 p |
$590 |
7 p |
610 + 5 p = 4 u --- (1)
590 + 7 p = 5 u --- (2)
Make p the same.
(1)
x 74270 +
35 p = 28 u
35 p = 28 u - 4270 --- (3)
(2)
x 52950 +
35 p = 25 u
35 p = 25 u - 2950 --- (4)
(3) = (4)
28 u - 4270 = 25 u - 2950
28 u - 25 u = 4270 - 2950
3 u = 1320
1 u = 1320 ÷ 3 = 440
(a)
Luis's salary
= 4 u
= 4 x 440
= $1760
(b)
David's salary
= 5 u
= 5 x 440
= $2200
Answer(s): (a) $1760; (b) $2200
