Valen, Albert and Riordan had the same number of marbles. Riordan gave 0.6 of his marbles to Albert. Then Albert gave 0.35 of his marbles to Valen. Finally, after Albert gave 24 marbles to Riordan, he had the same number of marbles as Riordan. How many marbles did Riordan have at first?
| |
Valen |
Albert |
Riordan |
| Before |
1 u |
1 u |
1 u |
| Change 1 |
|
+ 0.6 u |
- 0.6 u |
| After 1 |
1 u |
1.6 u |
0.4 u |
| Change 2 |
+ 0.56 u |
- 0.56 u |
|
| After 2 |
1.56 u |
1.04 u |
0.4 u |
| Change 3 |
|
- 24 |
+ 24 |
| After 3 |
1.56 u |
1.04 u - 24 |
0.4 u + 24 |
Number of marbles that Albert gave to Valen
= 0.35 x 1.6 u
= 0.56 u
The number of marbles that Albert and Riordan had in the end is the same.
1.04 u - 24 = 0.4 u + 24
1.04 u - 0.4 u = 24 + 24
0.64 u = 48
1 u = 48 ÷ 0.64 = 75
Number of marbles that Riordan had at first
= 1 u
= 75
Answer(s): 75
