PSLE Mark, Ian and Owen had 180 stickers altogether. Mark gave
320 of his stickers to Ian and
14 of his stickers to Owen. After that, all three boys had the same number of stickers. What was the difference in the number of stickers between Ian and Owen at first?
|
Mark |
Ian |
Owen |
Total |
Before |
20 u |
9 u |
7 u |
36 u |
Change 1 |
- 3 u |
+ 3 u |
|
|
Change 2 |
- 5 u |
|
+ 5 u |
|
After |
12 u |
12 u |
12 u |
36 u |
Comparing between Mark, Ian and Owen in the end |
1x12 = 12 u |
1x12 = 12 u |
1x12 = 12 u |
3x12 = 36 u |
Fraction of stickers that Mark had left
= 1 -
320 -
14 = 1 -
320 -
520 =
1220 Total number of stickers
= 3 x 12 u
= 36 u
36 u = 180
1 u = 180 ÷ 36 = 5
Difference in the number of stickers between Ian and Owen at first
= 9 u - 7 u
= 2 u
= 2 x 5
= 10
Answer(s): 10