PSLE Brandon had a total of 256 red and blue pens. After selling an equal number of both types, he had
14 of the red pens and
34 of the blue ones left. What was the total number of pens left?
Fraction of the red pens sold
= 1 -
14 =
34 Fraction of the blue pens sold
= 1 -
34 =
14 The number of red pens and blue pens sold is the same.
Make the numerators the same.
LCM of 3 and 1 = 3
34 Long pens =
14 Short pens
3x14x1 Long pens =
1x34x3 Short pens
34 Long pens =
312 Short pens
|
Long |
Short |
Total |
Before |
4 u |
12 u |
16 u |
Change |
- 3 u |
- 3 u |
- 6 u |
After |
1 u |
9 u |
10 u |
Total number of pens at first
= 4 u + 12 u
= 16 u
16 u = 256
1 u = 256 ÷ 16 = 16
Total number of pens left
= 1 u + 9 u
= 10 u
= 10 x 16
= 160
Answer(s): 160