Science calculations

Maths questions often start with the command words 'calculate' or 'determine'. They will then have a blank space for you to show your working. It is important that you show your working; don’t just write the answer down. You might earn marks for your working even if you get the answer incorrect.

In some maths questions you will be required to give the units. This may earn you an additional mark. Don't forget to check whether you need to do this.

Maths questions might include graphs and tables as well as calculations. Don't forget to take a ruler and calculator.

If drawing graphs, make sure you:

put the independent variable on the x-axis and the dependant variable on the y-axis
construct regular scales for the axes
label the axes appropriate
plot each point accurately
decide whether the origin should be used as a data point
draw a straight or curved line of best fit

If you are asked to calculate an answer and it has lots of decimal places, don't forget to use the same number of significant figures as the data in the question. For example, if two significant figures are used in the question, then usually your answer would also be to two significant figures. Don't forget to check your rounding.

Sample question 1 - Foundation

Question

Look at these tables.

They show the death rates from coronary heart disease (CHD) in the UK in 2008.

These death rates from CHD are per 100 000 of the population.

Age 55 - 64

Men	Women
175	47

Men	175
Women	47

Age 65 - 74

Men	Women
443	179

Men	443
Women	179

In 2008 the total number of deaths per 100 000 in both age ranges was 844.

What percentage of these deaths were women? [1 mark]

A	5.6%
B	21.2%
C	22.6%
D	26.8%

A
5.6%

B
21.2%

C
22.6%

D
26.8%

OCR Gateway, GCE Biology, Paper J247, 2016.

Sample question 2 - Foundation

Question

The following data was collected in two different school fields. Complete the table by calculating the mean value of clover plants per quadrat in each field. Give your answer to one decimal place. [2 marks]

Quadrat	1	2	3	4	5	6	7	8	Mean
Field 1	3	5	6	2	3	1	4	5
Field 2	0	0	2	3	4	1	0	2

Quadrat
1
2
3
4
5
6
7
8
Mean

Field 1
3
5
6
2
3
1
4
5

Field 2
0
0
2
3
4
1
0
2

This question has been written by a Bitesize consultant as a suggestion to the type of question that may appear in an exam paper.

Sample question 3 - Higher

Question

A farmer genetically modified her crops so that they released a toxin. This stopped them being eaten by pests. Before she genetically modified her crops her yield of crops was 100 kg per year. Now that she has genetically modified them her yield is 225 kg per year.

What is the percentage increase in the yield of the farmer’s crops? Show your working. [2 marks]

This question has been written by a Bitesize consultant as a suggestion to the type of question that may appear in an exam paper.

Sample exam questions - global challenges - OCR Gateway Science calculations