PSLEMary and Gabby went shopping together with a total amount of $103.80. Mary spent 2 times as much as Gabby. The amount Gabby had left was $26 more than what she had spent. She had 2 times as much money left as Mary.
(a) How much money did Gabby spend?
(b) How much money did Mary have at first?
|
Mary |
Gabby |
Total |
Before |
2.5 u + 13 |
2 u + 26 |
103.80 |
Change |
- 2 u |
- 1 u |
|
After |
0.5 u + 13 |
1 u + 26 |
|
(a)
Total amount that Mary and Gabby had at first
= (2.5 u + 13) + (2 u + 26)
= 2.5 u + 2 u + 13 + 26
= 4.5 u + 39
4.5 u + 39 = 103.8
4.5 u = 103.8 - 39
4.5 u = 64.8
1 u = 64.8 ÷ 4.5 = 14.4
Amount that Gabby had at first
= 1 u
= $14.40
(b)
Amount that Mary had at first
= 2.5 u + 13
= (2.5 x 14.4) + 13
= 36 + 13
= $49
Answer(s): (a) $14.40; (b) $49