Min, Penelope, Kathy and Sarah went to buy a gift for their grandfather. They shared the cost equally among themselves. However, Sarah forgot to bring her money. So, the other 3 girls paid for the gift first. Kathy paid
35 of the amount Min and Penelope paid. Penelope paid $2 more than Min. The next day, Sarah returned $4 to Kathy and some money to Min and Penelope. How much did Sarah return to
- Min?
- Penelope?
|
Min |
Penelope |
Kathy |
Sarah |
Total |
Comparing the amounts 3 girls paid first |
5 u
|
3 u
|
|
8 u
|
Comparing the amounts 2 girls paid first |
1 p
|
1 p + 2
|
|
|
|
Amounts that each girl paid for Sarah first |
- ? |
- ? |
- 4
|
+ 4 + ? |
|
Comparing the amounts each girl should pay |
1x2 = 2 u |
1x2 = 2 u |
1x2 = 2 u |
1x2 = 2 u |
4x2 = 8 u |
(a)
The total amount that the 4 girls paid is repeated. Make the total amount the same. LCM of 4 and 8 is 8.
Extra amount that Kathy paid
= 3 u - 2 u
= 1 u
1 u = 4
Total amount that Min and Penelope paid at first
= 5 u
= 5 x 4
= $20
1 p + 1 p + 2 = 20
2 p = 20 - 2
2 p = 18
1 p = 18 ÷ 2 = 9
Amount that Sarah needed to pay Min
= 1 p - 2 u
= 9 - 2 x 4
= 9 - 8
= $1
(b)
Amount that Sarah needed to pay Penelope
= (1 p + 2) - 2 u
= (9 + 2) - 2 x 4
= 11 - 8
= $3
Answer(s): (a) $1; (b) $3