Billy had $120 less than Ken. If Ken spends $70 and Billy's mother gave Billy $1010, Ken will have
16 as much money as Billy. How much money did Billy and Ken have?
| |
Make p the same
(1)x6 = (3) |
Billy
(1) |
Ken
(2) |
| Before |
6 u |
1 u |
1 u + 120 |
| Change |
- 420 |
- 70 |
+ 1010 |
| After |
6 p |
1 p |
6 p |
Since Billy had $120 less than Ken, this means Ken had $120 more than Billy.
1 u - 70 = 1 p --- (1)
1 u + 120 + 1010 = 6 p
1 u + 1130 =
6 p --- (2)
Make p the same.
(1)
x6
6 u - 420 =
6 p --- (3)
(3) = (2)
6 u - 420 = 1 u + 1130
6 u - 1 u = 1130 + 420
5 u = 1550
1 u = 1550 ÷ 5 = 310
Total amount that Billy and Ken had
= 1 u + 1 u + 120
= 2 u + 120
= 2 x 310 + 120
= 620 + 120
= $740
Answer(s): $740
