Luis had $100 less than Fred. If Fred spends $110 and Luis's mother gave Luis $480, Fred will have
14 as much money as Luis. How much money did Luis and Fred have?
| |
Make p the same
(1)x4 = (3) |
Luis
(1) |
Fred
(2) |
| Before |
4 u |
1 u |
1 u + 100 |
| Change |
- 440 |
- 110 |
+ 480 |
| After |
4 p |
1 p |
4 p |
Since Luis had $100 less than Fred, this means Fred had $100 more than Luis.
1 u - 110 = 1 p --- (1)
1 u + 100 + 480 = 4 p
1 u + 580 =
4 p --- (2)
Make p the same.
(1)
x4
4 u - 440 =
4 p --- (3)
(3) = (2)
4 u - 440 = 1 u + 580
4 u - 1 u = 580 + 440
3 u = 1020
1 u = 1020 ÷ 3 = 340
Total amount that Luis and Fred had
= 1 u + 1 u + 100
= 2 u + 100
= 2 x 340 + 100
= 680 + 100
= $780
Answer(s): $780
