Carl had a total of 72 notes. The notes are $2 notes and $10 notes. After he spent 75% of the $2 notes and 80% of the $10 notes on one gas stove, he was left with 4 times as many $10 notes as $2 notes. How much did the gas stove cost?
|
$2 |
$10 |
Before |
4x1 = 4 u |
5x4 = 20 u
|
Change |
- 3x1 = - 3 u |
- 4x4 = - 16 u
|
After |
1x1 = 1 u |
1x4 = 4 u |
Comparing $2 and $10 in the end |
1x1 = 1 u
|
4x1 = 4 u |
75% of $2 notes =
75
100 of $2 notes =
34 of $2 notes
80% of $10 notes =
80100 of $10 notes =
45 of $10 notes
The number of $2 notes in the end is repeated. Make the number of $2 notes the same. LCM of 1 and 4 is 4.
The number of $10 notes in the end is repeated. Make the number of $10 notes the same. LCM of 1 and 1 is 1.
Number of notes at first
= 4 u + 20 u
= 24 u
24 u = 72
1 u = 72 ÷ 24 = 3
|
$2 |
$10 |
Number |
3 u |
16 u |
Value |
2 |
10 |
Total value |
6 u |
160 u |
Value of $2 spent
= 3 u x 2
= 6 u
Value of $10 spent
= 16 u x 10
= 160 u
Price of the gas stove
= 6 u + 160 u
= 166 u
= 166 x 3
= $498
Answer(s): $498