PSLE Cody had a total of 323 long and short rulers. After selling an equal number of both types, he had
14 of the long rulers and
45 of the short ones left. What was the total number of rulers left?
Fraction of the long rulers sold
= 1 -
14 =
34 Fraction of the short rulers sold
= 1 -
45 =
15 The number of long rulers and short rulers sold is the same.
Make the numerators the same.
LCM of 3 and 1 = 3
34 Long rulers =
15 Short rulers
3x14x1 Long rulers =
1x35x3 Short rulers
34 Long rulers =
315 Short rulers
|
Long |
Short |
Total |
Before |
4 u |
15 u |
19 u |
Change |
- 3 u |
- 3 u |
- 6 u |
After |
1 u |
12 u |
13 u |
Total number of rulers at first
= 4 u + 15 u
= 19 u
19 u = 323
1 u = 323 ÷ 19 = 17
Total number of rulers left
= 1 u + 12 u
= 13 u
= 13 x 17
= 221
Answer(s): 221