GCSE Maths - 30 min Quiz WC 18th Jan 21

What is 2572 to one significant figure?

Answer explanation

You have just one number and everything else is zeros. So you look at the 2 and see if the next number along is 5 or above. If it is it bumps the 2 up to a 3. Then you change the rest of the numbers to zeros.

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.A.3

what is 25.465 to 2 decimal places?

Answer explanation

The 6 is two places from the decimal. The next number to the right is 5 so this pushes the 6 up to a 7.

Tags

CCSS.5.NBT.A.4

Work out  $5+(10−2)^2$    

Answer explanation

This is BIDMAS. Do the brackets first 10-2 = 8. Then do the indices which is the  $8^2$  = 64. Then add on the 5

Tags

CCSS.7.NS.A.3

1. Arrange in order from largest to smallest. 21%, 1/4, 16%, 0.2, 1/6

• 21%, 1/4, 16%, 0.2, 1/6

• 1/4, 21%, 0.2, 1/6, 16%

• 16%, 0.2, 1/6, 21%, 1/4

• 21%, 0.2, 1/6, 1/4, 16%

Answer explanation

Convert everything to decimals. 21% is 0.21. 1/4 is one divided by 4 which is 0.25. 16% is 0.16. 0.2 just stays the same. 1/6 is 1 divided by 6 which is 0.16666. They are then easy to compare.

A car cost £11,000 plus 20% VAT. How much will the car be to buy? (try to put the £ sign before your answer and the comma to show where the thousands are)

Answer explanation

You need to find 20% of £11,000. You can divide £11,000 by 100 to get 1% which is £110. You then times that by 20 to get 20%. This will be £2200. The last thing to do is to add this onto the original number. £11,000 +£2200

Tags

CCSS.6.RP.A.3C

In the 25% off sale an Iphone is reduced to £375. What was its original price?

Answer explanation

As the £375 is the price after 25% was taken off it is only 75% of the original amount. If you divide £375 x 75% you find out that 1% is £5. If you times that by 100% you find out what 100% was.

Tags

CCSS.6.RP.A.3C

Jim, Sarah and Josh share 30 sweets between them in the ratio 4:6:5. How many sweets will Josh Get?

Answer explanation

Add up the ratio. 4:6:5 to give 15 parts. Divide the number of sweets by the number of parts. This is 30 $\div$ 15 = 2 sweets per part. Josh get 5 parts so he get 5 x 2 sweets.

What is the volume of this shape? You must put down the correct units. (I.E cm, cm2 or cm3)

Answer explanation

You just times the 3 numbers together which gives 900. the units are cm but as it is volume it is cm $3$

Tags

CCSS.7.G.B.6

What is the area of this shape? You might have to use the numbers on the diagram to work out any missing numbers you need. You must put down the units.(I.E cm, cm2 or cm3)

Answer explanation

Divide the shape into two rectangles. The top of the "T" shape is 20 wide and you can work out its height which is 16-9 = 7cm. 20 x 7 = 140cm2. The bottom of the "T" shape is 9 high and 7 wide so 63cm2. Add these together and you get 203cm2.

Tags

CCSS.6.G.A.1

What is the area of this traingle.? You must put in the units (I.E cm, cm2 or cm3)

Answer explanation

The area of a triangle is 1/2 Base x height. For this triangle it is 1/2 x 6 x8. this is 1/2 of 48 = 24cm2

Tags

CCSS.6.G.A.1