Penelope, Emily, Tiffany and Cathy went to buy a souvenir for their grandmother. They shared the cost equally among themselves. However, Cathy forgot to bring her money. So, the other 3 girls paid for the souvenir first. Tiffany paid
511 of the amount Penelope and Emily paid. Emily paid $2 more than Penelope. The next day, Cathy returned $2 to Tiffany and some money to Penelope and Emily. How much did Cathy return to
- Penelope?
- Emily?
|
Penelope |
Emily |
Tiffany |
Cathy |
Total |
Comparing the amounts 3 girls paid first |
11 u
|
5 u
|
|
16 u
|
Comparing the amounts 2 girls paid first |
1 p
|
1 p + 2
|
|
|
|
Amounts that each girl paid for Cathy first |
- ? |
- ? |
- 2
|
+ 2 + ? |
|
Comparing the amounts each girl should pay |
1x4 = 4 u |
1x4 = 4 u |
1x4 = 4 u |
1x4 = 4 u |
4x4 = 16 u |
(a)
The total amount that the 4 girls paid is repeated. Make the total amount the same. LCM of 4 and 16 is 16.
Extra amount that Tiffany paid
= 5 u - 4 u
= 1 u
1 u = 2
Total amount that Penelope and Emily paid at first
= 11 u
= 11 x 2
= $22
1 p + 1 p + 2 = 22
2 p = 22 - 2
2 p = 20
1 p = 20 ÷ 2 = 10
Amount that Cathy needed to pay Penelope
= 1 p - 4 u
= 10 - 4 x 2
= 10 - 8
= $2
(b)
Amount that Cathy needed to pay Emily
= (1 p + 2) - 4 u
= (10 + 2) - 4 x 2
= 12 - 8
= $4
Answer(s): (a) $2; (b) $4