A bag of marbles was distributed equally among 18 boys. When 9 of these boys gave up
25 of their share, the rest of the boys received 10 more marbles each. How many marbles were there in the bag?
| |
Marbles given up |
Marbles received |
Total marbles |
| Number |
9 |
9 |
18 |
| Value |
2 u |
10 |
5 u |
| Total value |
18 u |
90 |
90 u |
Number of boys who received the extra marbles
= 18 - 9
= 9
Total number of extra marbles received by the rest of the boys
= 9 x 10
= 90
Total number of marbles given up
= 9 x 2 u
= 18 u
18 u = 90
1 u = 90 ÷ 18 = 5
Total number of marbles for 18 boys
= 18 x 5 u
= 90 u
= 90 x 5
= 450
Answer: 450
