(Use Model, branch or unit methods to work out the solution)
1. In a class of 40 pupils, ½ the number of boys is equal to ¾ the number of girls. How many more boys than girls are there in the class?
2. 0.5 of Ling Yuan’s sum of money is equal to 3/5 of Karen’s sum of money. If Ling Yuan has $24 more than Karen, how much do they have altogether? (Hint : Express the decimal as fraction)
3. In a school, 0.6 of the girls and 0.4 of the boys take part in CCAs. There is an equal number of boys and girls who do not take part in CCAs. If 480 pupils do not take part in CCAs, how many pupils are there in the school?
4. Mrs Tu baked a total of 450 almond cookies and chocolate cookies. After she gave 0.6 of the almond cookies and 0.5 of the chocolate cookies to her friends, she was left with an equal number of almond cookies and chocolate cookies. How many chocolate cookies had she left?
5. Mark and Rosy had a total of $850. After Rosy spent ¼ of her money and Mark spent ½ of his money, both had an equal amount of money left. Find the total amount of money each had at first.
6. Ben had 96 more stickers than Calvin. Calvin used ¾ of his stickers and Ben used 5/6 of his stickers. In the end, Ben had twice as many stickers as Calvin. Find the number of stickers Calvin had at first
7. A bag contained some red marbles and green marbles. 0.2 of the red marbles and 0.6 of the green marbles were removed. In the end, there were half as many red marbles as green marbles. Given that there were 30 more green marbles than red marbles at first, find the number of red marbles in the bag at first.
8. 2/3 of John’s savings is equal to 4/5 of Darren’s savings. John saves $20 more than Darren. How much does Darren save?
9. 2/3 of Sunny’s marbles is equal to 3/5 of Tim’s marbles. If Sunny has 4 marbles less than Tim, how many marbles does Tim have?
10. There are 60 more buttons than marbles in a box. 0.4 of the buttons is equal to 4/7 of the marbles. How many buttons are there in the box? How many buttons and marbles are there in the box altogether?