PSLE Reggie had a total of 285 short and long rulers. After selling an equal number of both types, he had
14 of the short rulers and
45 of the long ones left. What was the total number of rulers left?
Fraction of the short rulers sold
= 1 -
14 =
34 Fraction of the long rulers sold
= 1 -
45 =
15 The number of short rulers and long 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 = 285
1 u = 285 ÷ 19 = 15
Total number of rulers left
= 1 u + 12 u
= 13 u
= 13 x 15
= 195
Answer(s): 195