Hazel has a bag containing some pink and silver erasers. If she removes 2 pink erasers, 30% of the erasers in the bag are silver. If she removes another 20 silver erasers, 20% of the erasers in the bag are silver. How many pink erasers are in the bag?
| |
Pink erasers |
Silver erasers |
| Before |
28 u + 2 |
12 u |
| Change 1 |
- 2 |
|
| After 1 |
7x4 =
28 u |
3x4 =
12 u |
| Change 2 |
|
- 20 |
| After 2 |
4x7 =
28 u |
1x7 =
7 u |
30% =
30100 =
31020% =
20100 =
15The number of pink erasers remains unchanged at the second change when she removes another 20 silver erasers. Make the number of pink erasers the same at the second change. LCM of 7 and 4 is 28.
Number of silver erasers removed
= 12 u - 7 u
= 5 u
5 u = 20
1 u = 20 ÷ 5 = 4
Number of pink erasers at first
= 28 u + 2
= 28 x 4 + 2
= 112 + 2
= 114
Answer(s): 114
