Brandon, Billy, Ian and David bought a home theater system for their aunt. Brandon paid
13 of what the rest paid. Billy paid
14 of what the rest paid. Ian paid
15 of what the rest paid. David paid $40 more than Brandon. How much did the home theater system cost?
| Brandon |
Billy |
Ian |
David |
Total |
| 1x15 |
|
|
|
4x15 |
| |
1x12 |
|
|
5x12 |
| |
|
1x10 |
|
6x10 |
| 15 u |
12 u |
10 u |
23 u |
60 u |
The cost of the home theater system is repeated. Make the cost of the home theater system the same. LCM of 4, 5 and 6 is 60.
Amount that David had
= 60 u - (15 u + 12 u + 10 u)
= 23 u
Amount that David paid more than Brandon
= 23 u - 15 u
= 8 u
8 u = 40
1 u = 40 ÷ 8 = 5
Cost of the home theater system
= 60 u
= 60 x 5
= $300
Answer(s): $300
