Level 3
To fill a tank measuring 50 cm by 20 cm by 40 cm completely, it takes Tap A 4 minutes while it takes Tap B only 12 minutes. How long will it take to completely fill the container with water if both the taps are turned on at the same time and 8 cubic containers of edges 10 cm, filled to the brim with water are poured into the tank?
5 m
Level 2
A number when rounded off to the nearest hundred is 1800. What is the largest possible number?
2 m
Level 2
I am a whole number. The sum of all my digits is 20. If you round me off to the nearest ten, you will get 970. If you round me off to the nearest hundred, you will get 1000. Who am I?
4 m
Level 2
I am a 3-digit number. I am divisible by 7. If you round me off to the nearest hundred, you will get 500. If you round me off to the nearest ten, you will also get 500. Who am I?
4 m
Level 3
I am an even number. When 1 is added to me and I am rounded off to the nearest ten, I become 660. When 1 is subtracted from me and I am rounded off to the nearest ten, I become 650. What number am I?
4 m
Level 3
Jonathan wants to purchase a new car which costs $134850. Jonathan will pay a monthly instalment over a period of 5 years after paying a downpayment of $12850. How much is each monthly instalment? Round your answer off to the nearest thousand.
4 m
Level 1
What is the smallest number possible when rounded off to the nearest 100 is 530000?
1 m
Level 3
The figure shows a rectangle with its corners cut out. Each of the 4 identical corners cut out is a quarter circle. The ratio of the length of the rectangle to its breadth is 13 : 5.
  1. What is the radius of each quarter circle?
  2. What is the perimeter of the shaded part. Take π = 3.14. Give your answer correct to 1 decimal place.
5 m
Level 3
The figure is made up of a big quadrant OWY a small quadrant OVZ and a square VXZO. The radius of the big quadrant OWY is 12cm. The area of the big quadrant is twice the area of the small quadrant OVZ. Using the calculator value of π, find the area of the shaded parts, correct to 2 decimal places.
5 m
Level 3
The figure is make up of 3 circles. The small circle has centre O and a radius of 6 cm. The big circle, has centre O and a radius of 10 cm. The diameter of the big circle cuts through the centre of the medium-sized circle and the small circle. The three regions formed are indicated as X, Y and Z.
  1. Find the radius of the medium-sized circle.
  2. Find the area of region Z. Use a calculator to obtain the value of π. (Round off to nearest 2 decimal places).
  3. Express the area of the region Y as a ratio to the area of region X.
5 m