Oscar, Rael and Colin collected erasers in the ratio of 12 : 5 : 7. After Colin gave
310 to Oscar and Rael, Colin had 410 less erasers than Oscar. The number of erasers that Rael had increased by 20%. How many erasers did Oscar and Colin have in the end?
| |
Oscar |
Rael |
Colin |
| Before |
12 u |
5 u |
7 u |
| Change |
+ 1.1 u |
+ 1 u |
- 2.1 u |
| After |
13.1 u |
6 u |
4.9 u |
Number of erasers that Colin gave to Oscar and Rael
=
310 x 7 u
= 2.1 u
Number of erasers that Rael received from Colin
=
20100 x 5 u
= 1 u
Number of erasers that Oscar received from Colin
= 2.1 u - 1 u
= 1.1 u
Number of less erasers that Colin had less than Oscar
= 13.1 u - 4.9 u
= 8.2 u
8.2 u = 410
1 u = 410 ÷ 8.2 = 50
Number of erasers that Oscar and Colin had
= 13.1 u + 4.9 u
= 18 u
= 18 x 50
= 900
Answer(s): 900
