PSLE A box contained purple and orange beads. At first, the number of purple beads was
15 the number of orange beads. After
34 of the purple beads and
18 of the orange beads were used, 296 beads were left.
- What fraction of the beads were left? Leave your answer in the simplest form.
- How many beads were used?
|
Purple |
Orange |
Comparing purple beads and orange beads at first |
1x8 = 8 u |
5x8 = 40 u
|
Before
|
4x2 = 8 u |
8x5 = 40 u |
Change
|
- 3x2 = - 6 u |
- 1x5 = - 5 u |
After
|
1x2 = 2 u |
7x5 = 35 u |
(a)
The number of orange beads at first is repeated. Make the number of orange beads at first the same.
LCM of 5 and 8 is 40.
The number of purple beads at first is repeated.
Since the number of purple beads at first is 8 u, we make the total number of purple beads at first the same by multiplying 4 by 2 to become 8 u too.
Fraction of the beads left
=
2 + 358 + 40 =
3748 (b)
Number of beads left
= 2 u + 35 u
= 37 u
37 u = 296
1 u = 296 ÷ 37 = 8
Number of beads used
= 6 u + 5 u
= 11 u
= 11 x 8
= 88
Answer(s): (a)
3748; (b) 88