Maths worksheets for challenging problem sums

Related Skills
Skill Involving Changing quantities

1. Mother promised to give Jane $2.50 for each Math test she got above 91% and she would fine $1.50 for every Math test that she got below 91%. Jane succeeded in 7 times as many tests as she had not and received $48. How many tests did she take?

Ans :- Jane took 24 tests.

2. There are some red, blue, yellow and green balls in a basket, out of which 38 are not blue, 43 are not red and 47 are not green. There are 26 red and green balls altogether. How many balls are there in the basket?

Ans :- There are 58 balls in the basket
(yellow : 12 , red : 15, Green : 11, Blue : 20).

3. Stella and Theresa had a race running 6 times around a 400m track. Stella ran half the distance at an average speed of 450 m/min and slowed down for the second half at an average speed of 300 m/min. Theresa ran half of her total time at an average speed of 300 m/min and increased her speed to 450 m/min for the rest of the time.
(a)Who won the race?
(b)What distance did Theresa cover after half of her total?

Ans :- a) Theresa won the race
b) .

4. Granny went to the market with some money in her purse. She spent all her money on 6 oranges and 3 mangoes. Each mango cost $2.10 more than each orange. If she had bought 1 mango and 12 oranges, she would have $2.60 left. Find out how much money Granny went to market with.

Ans :- Grany went to market with $9.90

5. A and B are two different numbers selected from 1-100 inclusive. What is the largest value that A+B/A-B can have?

Ans :- 199 (A = 100, B = 99)

6. Ann and Ryan had a total of $42 and Ann had $2 more than Ryan. When Ryan donated 5 times as much money to charity as Ann, he found that Ann had 2 times as much money left. How much did Ryan have left?

Ans :- Ryan had left $10.

7. The difference between the area of square A and the area of square B is 200 cm². The length of one side of square A is thrice that of square B what is the perimeter of square A? (60 cm)

Ans :- The perimeter of square A is 60 cm.

8. If we count by 4s starting with 1, the following sequence is obtained 1, 5, 9, 13 … what is the 100th number in the sequence?

Ans :- 397.

9. The number 2, 4, 6 and 8 are a set of four consecutive even numbers. Suppose the sum of six consecutive even numbers is 270, what is the smallest of the six numbers?

Ans :- 40 .

10. There are 325 English and Chinese books in a library at first. When the number of English books increased by 25 and the number of Chinese books decreased by 5%, the number of English and Chinese books became 341. How many English books were there at first?

Ans :- At first there were 145 English books

11. Three boys A, B and C, shared their collection of stickers. A received 13 of the stickers. B and C shared the remaining stickers between themselves in the ratio 5:3. If A received 12 more stickers than C, how many stickers did they have in their collection?

Ans :- 144 stickers.