Xandra bought 6 laptops and 10 sandwich makers. Each laptop costs $391 more than each sandwich maker. She spent 20% of her money on the sandwich makers.
- How much did each laptop cost?
- How much did she spend altogether?
| |
Laptops |
Sandwich makers |
Total |
| Number |
6 |
10 |
|
| Value |
1 u + $391 |
1 u |
|
| Total value |
6 u + $2346 |
10 u |
|
Comparing amounts
spent on laptops
and sandwich makers |
80%
|
20% |
100% |
(a)
Amount that Xandra spent on the laptops
= 6(1 u + 391)
= 6 u + 2346
Amount that Xandra spent on the sandwich makers
= 10 x 1 u
= 10 u
Amount that Xandra spent on the laptops in percent
= 100% - 20%
= 80%
20% → 10 u
80% → 4 x 10 u = 40 u
40 u = 6 u + 2346
40 u - 6 u = 2346
34 u = 2346
1 u = 2346 ÷ 34 = 69
Cost of each laptop
= 69 + 391
= $460
(b)
100% → 10 u + 40 u = 50 u
Amount that Xandra spent altogether
= 50 u
= 50 x 69
= $3450
Answer(s): (a) $460; (b) $3450
