1) James, Keith and Leston had a total of 640 toy cars. James had the least number of toy cars. The ratio of Keith's toy cars to Leston's toy cars was 5 : 4 at first. After James and Keith had each lost half of their toy cars, Keith had 100 more toy cars than James. Given that the three boys had 440 toy cars left, how many toy cars did James have at first?

Ans :- 100.

2) A baker had a total of 120 pies and muffins in the ratio 3 : 5. After he sold an equal number of pies and muffins, the number of pies and muffins left was in the ratio 3 : 8. How many pies and muffins did he sell altogether?

Ans :- 54.

3) Jane had a total of 156 red and yellow beads in the ratio 7 : 6. After she gave away an equal number of each type of bead, the number of red and yellow beads left was in the ratio 7 : 3. How many beads did she give away altogether?

Ans :- 126 beads.

4) Class A and Class B have the same number of pupils. The ratio of the number of boys in Class A to the number of boys in Class B is 3:2. The ratio of the number of girls in Class A to the number of girls in Class B is 3:5. Find the ratio of the number of boys to the number of girls in Class A.

Ans :- 2 : 1.

5) Jane had a total of 156 red and yellow beads in the ratio 7 : 6. After she gave away an equal number of each type of bead, the number of red and yellow beads left was in the ratio 7 : 3. How many beads did she give away altogether?

Ans :- 126 beads.