Mrs Koh gave Cathy and Jane some money each on Tuesday. On Wednesday, Cathy gave
14 of the amount she had to Jane. On Thursday, Jane gave
15 of the amount she had to Cathy. In the end, Cathy had $30 and Jane had $12. How much did Jane had more than Cathy at first?
| |
Cathy |
Jane |
Total |
| Before 1 |
4 u |
? |
$42 |
| Change 1 |
- 1 u |
+ 1 u |
|
| After 1 |
3 u |
5 p |
$42 |
| Before 2 |
$30 - 1 p |
5 p |
$42 |
| Change 2 |
+ 1 p |
- 1 p |
|
After 2 |
$30 |
4 p
($12) |
$42 |
Amount that Jane had in the end = 4 p
4 p = 12
1 p = 12 ÷ 4 = 3
Working backwards.
Amount that Cathy had after giving to Jane on Wednesday
= 30 - 1 p
= 30 - 3
= $27
3 u = 27
1 u = 27 ÷ 3 = 9
Amount that Cathy had at first
= 4 u
= 4 x 9
= $36
Total amount that Cathy and Jane had
= 30 + 12
= $42
Amount that Jane had at first
= 42 - 36
= $6
Amount that Cathy had more than Jane
= 36 - 6
= $30
Answer(s): $30
