Jenson has 10% as many erasers as Rael. If Jenson gives away 20% of the erasers and Rael gives away 40% of his erasers, they will have 68 erasers altogether. How many erasers do the two of them have?
| |
Jenson |
Rael |
Total |
Comparing Jenson
and Rael at first |
1x5 =
5 u |
10x5 =
50 u |
|
| Before |
5x1 =
5 u |
5x10 =
50 u |
|
| Change |
- 1x1 =
- 1 u |
- 2x10 =
- 20 u |
|
| After |
4x1 =
4 u |
3x10 =
30 u |
68 |
10% =
10100 =
110 20% =
20100 =
15 40% =
40100 =
25 The number of erasers that Jenson has at first is repeated. Make the number of erasers that Jenson has the same. LCM of 1 and 5 is 5 u.
The number of erasers that Rael has at first is repeated. Make the number of erasers that Rael has the same. LCM of 10 and 5 is 50 u.
Number of erasers in the end
= 4 u + 30 u
= 34 u
34 u = 68
1 u = 68 ÷ 34 = 2
Total number of erasers that the two of them have
= 5 u + 50 u
= 55 u
= 55 x 2
= 110
Answer(s): 110
