PSLE Julian had a total of 380 short and long rulers. After selling an equal number of both types, he had
16 of the short rulers and
14 of the long ones left. What was the total number of rulers left?
Fraction of the short rulers sold
= 1 -
16 =
56 Fraction of the long rulers sold
= 1 -
14 =
34 The number of short rulers and long rulers sold is the same.
Make the numerators the same.
LCM of 5 and 3 = 15
56 Long rulers =
34 Short rulers
5x36x3 Long rulers =
3x54x5 Short rulers
1518 Long rulers =
1520 Short rulers
|
Long |
Short |
Total |
Before |
18 u |
20 u |
38 u |
Change |
- 15 u |
- 15 u |
- 30 u |
After |
3 u |
5 u |
8 u |
Total number of rulers at first
= 18 u + 20 u
= 38 u
38 u = 380
1 u = 380 ÷ 38 = 10
Total number of rulers left
= 3 u + 5 u
= 8 u
= 8 x 10
= 80
Answer(s): 80