Carl had a total of 119 notes. The notes are $10 notes and $2 notes. After he spent 80% of the $10 notes and 75% of the $2 notes on one refrigerator, he was left with 3 times as many $2 notes as $10 notes. How much did the refrigerator cost?
|
$10 |
$2 |
Before |
5x1 = 5 u |
4x3 = 12 u
|
Change |
- 4x1 = - 4 u |
- 3x3 = - 9 u
|
After |
1x1 = 1 u |
1x3 = 3 u |
Comparing $10 and $2 in the end |
1x1 = 1 u
|
3x1 = 3 u |
80% of $10 notes =
80
100 of $10 notes =
45 of $10 notes
75% of $2 notes =
75100 of $2 notes =
34 of $2 notes
The number of $10 notes in the end is repeated. Make the number of $10 notes the same. LCM of 1 and 3 is 3.
The number of $2 notes in the end is repeated. Make the number of $2 notes the same. LCM of 1 and 1 is 1.
Number of notes at first
= 5 u + 12 u
= 17 u
17 u = 119
1 u = 119 ÷ 17 = 7
|
$10 |
$2 |
Number |
4 u |
9 u |
Value |
10 |
2 |
Total value |
40 u |
18 u |
Value of $10 spent
= 4 u x 10
= 40 u
Value of $2 spent
= 9 u x 2
= 18 u
Price of the refrigerator
= 40 u + 18 u
= 58 u
= 58 x 7
= $406
Answer(s): $406