Mary bought 2 notebooks and 4 juicers. Each notebook costs $415 more than each juicer. She spent 25% of her money on the juicers.
- How much did each notebook cost?
- How much did she spend altogether?
| |
Notebooks |
Juicers |
Total |
| Number |
2 |
4 |
|
| Value |
1 u + $415 |
1 u |
|
| Total value |
2 u + $830 |
4 u |
|
Comparing amounts
spent on notebooks
and juicers |
75%
|
25% |
100% |
(a)
Amount that Mary spent on the notebooks
= 2(1 u + 415)
= 2 u + 830
Amount that Mary spent on the juicers
= 4 x 1 u
= 4 u
Amount that Mary spent on the notebooks in percent
= 100% - 25%
= 75%
25% → 4 u
75% → 3 x 4 u = 12 u
12 u = 2 u + 830
12 u - 2 u = 830
10 u = 830
1 u = 830 ÷ 10 = 83
Cost of each notebook
= 83 + 415
= $498
(b)
100% → 4 u + 12 u = 16 u
Amount that Mary spent altogether
= 16 u
= 16 x 83
= $1328
Answer(s): (a) $498; (b) $1328
