Tom, Ken and Calvin collected erasers in the ratio of 8 : 10 : 7. After Calvin gave
710 to Tom and Ken, Calvin had 272 less erasers than Tom. The number of erasers that Ken had increased by 40%. How many erasers did Tom and Calvin have in the end?
| |
Tom |
Ken |
Calvin |
| Before |
8 u |
10 u |
7 u |
| Change |
+ 0.9 u |
+ 4 u |
- 4.9 u |
| After |
8.9 u |
14 u |
2.1 u |
Number of erasers that Calvin gave to Tom and Ken
=
710 x 7 u
= 4.9 u
Number of erasers that Ken received from Calvin
=
40100 x 10 u
= 4 u
Number of erasers that Tom received from Calvin
= 4.9 u - 4 u
= 0.9 u
Number of less erasers that Calvin had less than Tom
= 8.9 u - 2.1 u
= 6.8 u
6.8 u = 272
1 u = 272 ÷ 6.8 = 40
Number of erasers that Tom and Calvin had
= 8.9 u + 2.1 u
= 11 u
= 11 x 40
= 440
Answer(s): 440
