PSLECindy and Erika went shopping together with a total amount of $136.80. Cindy spent 2 times as much as Erika. The amount Erika had left was $36 more than what she had spent. She had 2 times as much money left as Cindy.
(a) How much money did Erika spend?
(b) How much money did Cindy have at first?
|
Cindy |
Erika |
Total |
Before |
2.5 u + 18 |
2 u + 36 |
136.80 |
Change |
- 2 u |
- 1 u |
|
After |
0.5 u + 18 |
1 u + 36 |
|
(a)
Total amount that Cindy and Erika had at first
= (2.5 u + 18) + (2 u + 36)
= 2.5 u + 2 u + 18 + 36
= 4.5 u + 54
4.5 u + 54 = 136.8
4.5 u = 136.8 - 54
4.5 u = 82.8
1 u = 82.8 ÷ 4.5 = 18.4
Amount that Erika had at first
= 1 u
= $18.40
(b)
Amount that Cindy had at first
= 2.5 u + 18
= (2.5 x 18.4) + 18
= 46 + 18
= $64
Answer(s): (a) $18.40; (b) $64