Level 3
Tank E contained 4 times as many guppies as Tank F. When 10% of the guppies in Tank E and 10% of the guppies in Tank F were transferred to Tank G, Tank G had 120 guppies, which was 20% more guppies than before. How many less guppies were there in Tank F than Tank E in the end?
4 m
Level 3
Vincent had some pastries. 27 of them were tarts. The rest were cookies. He sold 35 of the tarts and 14 cookies. In the end, he had 131 pastries left. How many more tarts than cookies did he sell?
3 m
Level 3
Ali is b years old. Bill is four times as old as Ali and Calvin is 6 years younger than Bill.
  1. Express Calvin's age in terms of b.
  2. Ali is 10 years old as of now. ln how many years' time will Calvin be 3 times as old as Ali?
4 m
Level 3
Isabelle had $574 less than Jane. Jane spent 35 of her money and Isabelle spent 34 of her money. In the end, Jane had 3 times as much as Isabelle. Find the amount of money Isabelle had at first.
4 m
Level 3
Roger had two planks of the same length. He sawed one plank into equal parts of length 90 cm. In each part he drilled 6 small holes as shown in Figure 1. After that, he sawed the other plank into equal parts of length 1.5 m and in each part, he drilled 8 big holes as shown in Figure 2. When he finished drilling, he counted that there were 12 more small holes than big holes. If all the holes are spaced equally, how many holes were there altogether?
4 m