Flynn, Michael and Fabian had the same number of marbles. Fabian gave 0.5 of his marbles to Michael. Then Michael gave 0.25 of his marbles to Flynn. Finally, after Michael gave 20 marbles to Fabian, he had the same number of marbles as Fabian. How many marbles did Fabian have at first?
| |
Flynn |
Michael |
Fabian |
| Before |
1 u |
1 u |
1 u |
| Change 1 |
|
+ 0.5 u |
- 0.5 u |
| After 1 |
1 u |
1.5 u |
0.5 u |
| Change 2 |
+ 0.375 u |
- 0.375 u |
|
| After 2 |
1.375 u |
1.125 u |
0.5 u |
| Change 3 |
|
- 20 |
+ 20 |
| After 3 |
1.375 u |
1.125 u - 20 |
0.5 u + 20 |
Number of marbles that Michael gave to Flynn
= 0.25 x 1.5 u
= 0.375 u
The number of marbles that Michael and Fabian had in the end is the same.
1.125 u - 20 = 0.5 u + 20
1.125 u - 0.5 u = 20 + 20
0.625 u = 40
1 u = 40 ÷ 0.625 = 64
Number of marbles that Fabian had at first
= 1 u
= 64
Answer(s): 64
