Fanny bought 6 televisions and 7 lamps. Each television costs $440 more than each lamp. She spent 20% of her money on the lamps.
- How much did each television cost?
- How much did she spend altogether?
|
Televisions |
Lamps |
Total |
Number |
6 |
7 |
|
Value |
1 u + $440 |
1 u |
|
Total value |
6 u + $2640 |
7 u |
|
Comparing amounts spent on televisions and lamps |
80%
|
20% |
100% |
(a)
Amount that Fanny spent on the televisions
= 6(1 u + 440)
= 6 u + 2640
Amount that Fanny spent on the lamps
= 7 x 1 u
= 7 u
Amount that Fanny spent on the televisions in percent
= 100% - 20%
= 80%
20% → 7 u
80% → 4 x 7 u = 28 u
28 u = 6 u + 2640
28 u - 6 u = 2640
22 u = 2640
1 u = 2640 ÷ 22 = 120
Cost of each television
= 120 + 440
= $560
(b)
100% → 7 u + 28 u = 35 u
Amount that Fanny spent altogether
= 35 u
= 35 x 120
= $4200
Answer(s): (a) $560; (b) $4200