Level 2
A bag contains blue and green marbles in the ratio of 2 : 5. There is a total of 91 marbles in the bag. How many more blue marbles must be added into the bag so that the number of blue marbles will be the same as the number of green marbles?
Level 2
There was an equal number of boys and girls in the hall. When 10% of the girls left the hall, there were 5 more boys than girls remaining in the hall. How many children remained in the hall?