Fanny and Tina have 312 marbles altogether. Tina has thrice as many marbles as Fanny. How many marbles must Tina give to Fanny so that they have the same number of marbles?
| |
Fanny |
Tina |
Total |
| Before |
1 u |
3 u |
312 |
| Change |
+ ? |
- ? |
|
| After |
156 |
156 |
312 |
Total number of marbles that Fanny and Tina have
= 1 u + 3 u
= 4 u
4 u = 312
1 u = 312 ÷ 4 = 78
Number of marbles that Fanny and Tina each has in the end
= 312 ÷ 2
= 156
Number of marbles that Tina must give to Fanny
= 156 - 78
= 78
Answer(s): 78
