Carl had a total of 51 notes. The notes are $2 notes and $5 notes. After he spent 80% of the $2 notes and 75% of the $5 notes on one washing machine, he was left with 3 times as many $5 notes as $2 notes. How much did the washing machine cost?
|
$2 |
$5 |
Before |
5x1 = 5 u |
4x3 = 12 u
|
Change |
- 4x1 = - 4 u |
- 3x3 = - 9 u
|
After |
1x1 = 1 u |
1x3 = 3 u |
Comparing $2 and $5 in the end |
1x1 = 1 u
|
3x1 = 3 u |
80% of $2 notes =
80
100 of $2 notes =
45 of $2 notes
75% of $5 notes =
75100 of $5 notes =
34 of $5 notes
The number of $2 notes in the end is repeated. Make the number of $2 notes the same. LCM of 1 and 3 is 3.
The number of $5 notes in the end is repeated. Make the number of $5 notes the same. LCM of 1 and 1 is 1.
Number of notes at first
= 5 u + 12 u
= 17 u
17 u = 51
1 u = 51 ÷ 17 = 3
|
$2 |
$5 |
Number |
4 u |
9 u |
Value |
2 |
5 |
Total value |
8 u |
45 u |
Value of $2 spent
= 4 u x 2
= 8 u
Value of $5 spent
= 9 u x 5
= 45 u
Price of the washing machine
= 8 u + 45 u
= 53 u
= 53 x 3
= $159
Answer(s): $159