PSLE Zeph had a total of 208 long and short rulers. After selling an equal number of both types, he had
23 of the long rulers and
14 of the short ones left. What was the total number of rulers left?
Fraction of the long rulers sold
= 1 -
23 =
13 Fraction of the short rulers sold
= 1 -
14 =
34 The number of long rulers and short rulers sold is the same.
Make the numerators the same.
LCM of 1 and 3 = 3
13 Long rulers =
34 Short rulers
1x33x3 Long rulers =
3x14x1 Short rulers
39 Long rulers =
34 Short rulers
|
Long |
Short |
Total |
Before |
9 u |
4 u |
13 u |
Change |
- 3 u |
- 3 u |
- 6 u |
After |
6 u |
1 u |
7 u |
Total number of rulers at first
= 9 u + 4 u
= 13 u
13 u = 208
1 u = 208 ÷ 13 = 16
Total number of rulers left
= 6 u + 1 u
= 7 u
= 7 x 16
= 112
Answer(s): 112