Erika bought 2 washing machines and 4 slow cookers. Each washing machine costs $399 more than each slow cooker. She spent 20% of her money on the slow cookers.
- How much did each washing machine cost?
- How much did she spend altogether?
| |
Washing machines |
Slow cookers |
Total |
| Number |
2 |
4 |
|
| Value |
1 u + $399 |
1 u |
|
| Total value |
2 u + $798 |
4 u |
|
Comparing amounts
spent on washing machines
and slow cookers |
80%
|
20% |
100% |
(a)
Amount that Erika spent on the washing machines
= 2(1 u + 399)
= 2 u + 798
Amount that Erika spent on the slow cookers
= 4 x 1 u
= 4 u
Amount that Erika spent on the washing machines in percent
= 100% - 20%
= 80%
20% → 4 u
80% → 4 x 4 u = 16 u
16 u = 2 u + 798
16 u - 2 u = 798
14 u = 798
1 u = 798 ÷ 14 = 57
Cost of each washing machine
= 57 + 399
= $456
(b)
100% → 4 u + 16 u = 20 u
Amount that Erika spent altogether
= 20 u
= 20 x 57
= $1140
Answer(s): (a) $456; (b) $1140
