PSLE Valen had a total of 34 short and long erasers. After selling an equal number of both types, he had
13 of the short erasers and
14 of the long ones left. What was the total number of erasers left?
Fraction of the short erasers sold
= 1 -
13 =
23 Fraction of the long erasers sold
= 1 -
14 =
34 The number of short erasers and long erasers sold is the same.
Make the numerators the same.
LCM of 2 and 3 = 6
23 Long erasers =
34 Short erasers
2x33x3 Long erasers =
3x24x2 Short erasers
69 Long erasers =
68 Short erasers
|
Long |
Short |
Total |
Before |
9 u |
8 u |
17 u |
Change |
- 6 u |
- 6 u |
- 12 u |
After |
3 u |
2 u |
5 u |
Total number of erasers at first
= 9 u + 8 u
= 17 u
17 u = 34
1 u = 34 ÷ 17 = 2
Total number of erasers left
= 3 u + 2 u
= 5 u
= 5 x 2
= 10
Answer(s): 10