Question:

Level 3 PSLE

David has 8 large cubes and some small cubes. He placed them in a rectangular tank. The tank was filled to the brim exactly. The diagram shows the first layer of cubes.

David has 8 large cubes and some small cubes. He placed them in a rectangular tank. The tank was filled to the brim exactly. The diagram shows the first layer of cubes.

- How many small cubes does David have?
- The volume of the tank is 504 cm
^{3}. If the large cubes took up^{3}_{7}of the tank, What is the length of the edge of one small cube?

4 m

Level 3

Fill in the blanks.

The ratio of adults to children is 1 : 2.

The ratio of boys to girls is 3 : 5.

Use LCM and find the following.

4 m
Fill in the blanks.

The ratio of adults to children is 1 : 2.

The ratio of boys to girls is 3 : 5.

Use LCM and find the following.

- Number of adults = _____ u
- Number of boys = _____ u
- Difference in the number of boys and girls = _____ u
- Total number of people = _____ u

Level 1

Find the following values without a calculator.

2 m
Find the following values without a calculator.

- LCM of 2 and 8
- LCM of 3 and 18
- LCM of 12 and 20
- LCM of 2, 4 and 8

Level 2

Andrew wants to make a square with rectangular tiles each measuring 8 cm by 6 cm. How many such rectangular tiles must he use to make the smallest possible square?

Andrew wants to make a square with rectangular tiles each measuring 8 cm by 6 cm. How many such rectangular tiles must he use to make the smallest possible square?

2 m

Level 3

Irene has enough flour to bake either 21a tarts or 18 biscuits. If she has finished baking 5a tarts and 6 biscuits, how many more tarts can she still bake in terms of a?

2 m
Irene has enough flour to bake either 21a tarts or 18 biscuits. If she has finished baking 5a tarts and 6 biscuits, how many more tarts can she still bake in terms of a?

Level 3

The figure, not drawn to scale, shows 2 rectangles overlapping each other. The ratio of the shaded area to the area of Rectangle A is 3 : 8. The ratio of the shaded area to the area of Rectangle B is 2 : 5. Find the ratio of the unshaded area to the total area of the figure.

The figure, not drawn to scale, shows 2 rectangles overlapping each other. The ratio of the shaded area to the area of Rectangle A is 3 : 8. The ratio of the shaded area to the area of Rectangle B is 2 : 5. Find the ratio of the unshaded area to the total area of the figure.

3 m

Level 3

The figure, not drawn to scale, on the right shows 2 rectangles overlapping each other. The ratio of the shaded area to the area of Rectangle X is 4 : 9. The ratio of the shaded area to the area of Rectangle Y is 3 : 6. Find the ratio of the unshaded area to the total area of the figure.

The figure, not drawn to scale, on the right shows 2 rectangles overlapping each other. The ratio of the shaded area to the area of Rectangle X is 4 : 9. The ratio of the shaded area to the area of Rectangle Y is 3 : 6. Find the ratio of the unshaded area to the total area of the figure.

3 m

Level 3

At 7 a.m., a black car and a green car left the office and travelled at average speeds in opposite directions round a 25-km route. The black car took 15 minutes to complete each round while the green car took 20 minutes.

3 m
At 7 a.m., a black car and a green car left the office and travelled at average speeds in opposite directions round a 25-km route. The black car took 15 minutes to complete each round while the green car took 20 minutes.

- Find the speed of the black car.
- Find the speed of the green car.
- If the 2 cars travelled without any interval of rest, at what time would the 2 cars next meet again at the office?

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?

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

Level 3

Vivian and Kyle started cycling at uniform speeds from the same place in opposite direction round an 800-m forest trail. Vivian took 40 seconds to complete each round while Kyle took 50 seconds.

3 m
Vivian and Kyle started cycling at uniform speeds from the same place in opposite direction round an 800-m forest trail. Vivian took 40 seconds to complete each round while Kyle took 50 seconds.

- Find the distance covered per second by Vivian in m.
- Find the distance covered per second by Kyle in m.
- When the two cyclists next met again at the starting point, how far would Vivian have covered? Express the answer in km.