# Brush up your maths: Simple maths test 2010

## The test

There were ten questions:
1. 627 + 183 = ?

2. 20 – 3 × 5 = ?

3. Put these numbers in order of magnitude from smallest to biggest:
0.5   0.03   1   0.1   1.5   0.3   0.55   0.05

4. 0.001 is equal to which of the following?
1               1                   1
(a) –––     (b) ––––     (c) –––––
10             100             1000

5. ¾ + 0.6 = ?

6. If y = x – 2, what is the value of x when y = 6?

7. Write 3.75 million in figures.

8. √(32 + 42) = ?

9. What is 2½% of £10?

10. If cheese is £4.40 per kilogramme, what should I pay for 200 grammes?

1. 627 + 183 = 810

2. 20 – 3 × 5 = 5.
Note that the order of operations in maths is brackets, powers of, divide, multiply, add, subtract.

3. Put these numbers in order of magnitude from smallest to biggest:
0.5   0.03   1   0.1   1.5   0.3   0.55   0.05
gives us
0.03   0.05   0.1   0.3   0.5   0.55   1   1.5

4. 0.001 is equal to which of the following?
1               1                   1
(a) –––     (b) ––––     (c) –––––
10             100             1000

5. ¾ + 0.6 = 0.75 + 0.6 = 1.35.
I would also accept 1 7/20 or 27/20.

6. If y = x – 2, the value of x when y = 6 is 8.

7. Write 3.75 million in figures: 3,750,000.

8. √(32 + 42) = √(9 + 16) = √25 = 5.

9. 2½% of £10 = £0.25 = 25p.

10. If cheese is £4.40 per kilogramme, for 200 grammes I should pay £4.40 × 200/1000 = £0.88 = 88p.

There were 37 students. The numbers getting each possible score out of 10 were:

Score Count     %
0 0 0.0
1 0 0.0
2 0 0.0
3 0 0.0
4 2 5.4
5 4 10.8
6 1 2.7
7 4 10.8
8 5 13.5
9 8 21.6
10 13 35.1

We can present this graphically:

Hence 11 students got 7 or less, the score that I suggested meant that they should brush up their maths.

The question which caused most trouble was 2: 20 – 3 × 5 = ?. 48% got this wrong, all giving the answer 85. They got this by first subtracting 3 from 20 then multiplying 17 by 5. The rules of arithmetic are that we multiply before we add. We do not need brackets to make this clear. See part 1 of Brush up your maths.

We asked whether you panicked when you saw all those numbers. 19 said 'yes' to this. Not surprisingly, the panickers did worst, with mean score = 7.0, compared to 9.3 for those who did not panic.

These results were better than in previous years, well done.

Martin Bland
October, 2010.