Xylia bought 6 computers and 9 sandwich makers. Each computer costs $450 more than each sandwich maker. She spent 20% of her money on the sandwich makers.
- How much did each computer cost?
- How much did she spend altogether?
| |
Computers |
Sandwich makers |
Total |
| Number |
6 |
9 |
|
| Value |
1 u + $450 |
1 u |
|
| Total value |
6 u + $2700 |
9 u |
|
Comparing amounts
spent on computers
and sandwich makers |
80%
|
20% |
100% |
(a)
Amount that Xylia spent on the computers
= 6(1 u + 450)
= 6 u + 2700
Amount that Xylia spent on the sandwich makers
= 9 x 1 u
= 9 u
Amount that Xylia spent on the computers in percent
= 100% - 20%
= 80%
20% → 9 u
80% → 4 x 9 u = 36 u
36 u = 6 u + 2700
36 u - 6 u = 2700
30 u = 2700
1 u = 2700 ÷ 30 = 90
Cost of each computer
= 90 + 450
= $540
(b)
100% → 9 u + 36 u = 45 u
Amount that Xylia spent altogether
= 45 u
= 45 x 90
= $4050
Answer(s): (a) $540; (b) $4050
