Maths worksheets for challenging problem sums

Related Skills
Skill Involving Two or more Quantities With Fixed Total

1) Harem scored 11.8 seconds for his shuttle run test. His teacher allowed him to retake the test another 2 times. Harem's second timing was 90% of his first timing. His third timing was 0.9 seconds less than his second timing. Find the total time that he scored for the three tests. Round off your answer to 1 decimal place.

Ans :- 32.1 secpnds.

2) There are 4 nursery classes A, B, C and D, in Healthkidz School. The product of the number of children in Class A and Class B is 168. There are a total of 23 children in Class B and Class C, and a total of 25 children in Class B and Class A. The number of children in Class D is 57 of the number of children in Class A. How many children are there in Healthkidz school altogether?

Ans :- Altogethere there are 47 children .

3) In a water theme park, a small boat holds 4 people and a large boat holds 6 people. There are a total of 30 boats in the park and a total of 156 people on the boats. How many small boats are there in the part?

Ans :- There are 12 boats in the park.

4) A, B and C had a total weight of 115kg. After a year. A's weight was doubled, B's weight increased by 15kg and C's weight reduced by 5kg. As a result, A became twice heavy as B and B became twice heavy as C. what was B's weight at first?

Ans :- At first B's weight was 35 kg.

5) The ratio of the number of boys to the number of girls in a nursery was 4:5. In the first year, when 70 girls joined the nursery, there was a 35% increase in the number of girls. In the second year, some more children joined the nursery increased by another 20%. Find the overal increase in the number of children for 2 years.

Ans :- 86.

6) A competition consisted of 4 parts, A, B, C and D. Each part had a maximum score of 200 marks. Derek scored an average of 144 points for the 4 parts. He scored 168 points for part A. This was 8 points more than the score for part B. For the part C, his score was 34 of that for part A. To qualify for the second round of competition, he needed at least an average score of 80% for part B, C and D. By what percentage was he short of qualifying for the second round?

Ans :- a)12%

7) There are 12 boys in a group. The number of boys who can swim is 6 and the number of boys who can dive is 4. Among them, 2 boys can do both. Find the number of boys who do not know how to swim or dive at all.

Ans :- 3 boys do not know how to swim or dive at all.

8) A book is opened and the sum of the page number facing each other is 1993. What pages of the book had you turned to?

Ans :- 996,997

9) Robert is selling 3 computers for $8400 or 5 computers for $13400. Either transaction yields the same profit. If Robert sold 22 computers, how much profit did he make?

Ans :- He made profit of $5400

10) There are 3 different types of dictionaries sold in all book shop. The table below shows the thickness of one dictionary of each type.

Type Thicness (in cm)
Red 8
Blue 12
Green 15

A sales assistant stacked a few of each type of dictionary until they reached total height of 2 m. He realized that he has stacked up the same number of red and green dictionaries.
(a) How many red dictionaries were there in the rack?
(b) How many dictionaries are there in the stack in all?

Ans :- a) There are 4 red dictionary in the rack
b) In all there are 17 dictionaries

11) A ballpoint pen cost 8 times as an exercise book. John spent 25 of his money on exercise books and 13 of the remainder on 3 ballpoint pens. How many exercise books did he buy?

Ans :- 48 exercise books.