PSLE Zane had a total of 69 short and long erasers. After selling an equal number of both types, he had
14 of the short erasers and
35 of the long ones left. What was the total number of erasers left?
Fraction of the short erasers sold
= 1 -
14 =
34 Fraction of the long erasers sold
= 1 -
35 =
25 The number of short erasers and long erasers sold is the same.
Make the numerators the same.
LCM of 3 and 2 = 6
34 Long erasers =
25 Short erasers
3x24x2 Long erasers =
2x35x3 Short erasers
68 Long erasers =
615 Short erasers
|
Long |
Short |
Total |
Before |
8 u |
15 u |
23 u |
Change |
- 6 u |
- 6 u |
- 12 u |
After |
2 u |
9 u |
11 u |
Total number of erasers at first
= 8 u + 15 u
= 23 u
23 u = 69
1 u = 69 ÷ 23 = 3
Total number of erasers left
= 2 u + 9 u
= 11 u
= 11 x 3
= 33
Answer(s): 33