Lesson: Checking Methods L1-L2

• Mathematics
• Lower Secondary (Key Stage 3)

What is the most significant number in the number 789.65.

1. 7
2. 8
3. 9
4. 6

What is 178 rounded to 1 significant figure

1. 170
2. 180
3. 200
4. 100

What is 3564 rounded to 1 significant figure

1. 3000
2. 4000
3. 3600
4. 3500

Without working out the exact answer use estimation to work out which answer is the most likely to be correct to the question below
397 + 209

1. 606
2. 806
3. 506
4. 706

What is 543.50 to 1 significant figure,

1. 500
2. 540
3. 550
4. 600

Which of the following would be the best estimate for
1.9 x 197.6

1. 40
2. 400
3. 4000
4. 40,000

Craig buys 17 bottles of water at £1.62 each. Which calculation should Craig use to estimate the total cost?

1. 17 x 1.62
2. 17 x 1.60
3. 20 x 2
4. 20 x 1.62

Mr Blevins wants to buy a revision guide for each student.
There are 138 pupils.
The revision guides cost £3.75 each. Estimate how much the revision guides cost in total.

Joe drives around 82 miles each week. Estimate how many miles Joe drives in a year.

Jack needs to work out the area of a hall. he knows if he multiplies the length by the width he will get the area. The width is 4.4 metres and the length is 22.7 metres. Estimate the area of the hall.

34 x ? = 204

1. 8
2. 7
3. 6
4. 9

? x 6 = 128

1. 15
2. 16
3. 17
4. 18

? x 8= 416

1. 54
2. 52
3. 56
4. 58

Joe is asked to work out how many cinema tickets costing £4.50 she can buy with £144. She carries out the calculation below.
£144 ÷ 4.50 = 32
Write an inverse calculation to check Jo's answer.