Penelope, Joelle, Winnie and Betty jointly contributed to the cost of a present for their sister. Penelope's contribution is
89 of the total contribution made by the four girls. The ratio of Betty's contribution to the total of Joelle's and Winnie's contribution is 3 : 1. What is the total contribution by the four girls if Joelle's contribution is
13 of Winnie's contribution and the total amount contributed by Penelope and Betty is $2380?
Penelope |
Joelle |
Winnie |
Betty |
Total |
8x16 |
1x16 |
9x16 |
|
1x4
|
3x4 |
|
|
1x1 |
3x1 |
|
|
128 u |
1 u |
3 u |
12 u |
144 u |
Working backwards.
Total amount that Joelle and Winnie had is the combined repeated identity.
LCM of 1 and 4 = 4
Total amount that Joelle, Winnie and Betty had is the next combined repeated identity.
LCM of 1 and 16 = 16
Total amount contributed by Penelope and Betty
= 128 u + 12 u
= 140 u
140 u = 2380
1 u = 2380 ÷ 140 = $17
Total contribution by the four girls
= 144 u
= 144 x 17
= $2448
Answer(s): $2448