Ratio, proportion and percentages

This free course is available to start right now. Review the full course description and key learning outcomes and create an account and enrol if you want a free statement of participation.

Free course

# 3.1.1 Try some yourself

## Activity 17

Express each of the following percentages as fractions:

• (a) 40%

• (b) 8%

• (c) 70%

• (d)

• (a) 40%=

• (b) 8%=

• (c) 70%=

• (d)

## Activity 18

Express each of the following percentages as decimals:

• (a) 50%

• (b) 85%

• (c) 7%

• (d)

### Answer

• (a) 50% = = 0.5

• (b) 85% = =0.85

• (c) 7% = = 0.07

• (d)

## Activity 19

A survey was carried out on 840 couples to investigate family income. 75% of the women were in paid work; 90% of the men were in paid work; 18% of the couples had a joint income of less than £160 per week.

• (a) How many women were in paid work?

• (b) How many men were in paid work?

• (c) How many couples had a joint income of less than £160 per week?

### Answer

• (a) 75% of 840 = 0.75 × 840 = 630,

• so 630 women were in paid work.

• (b) 90% of 840 = 0.9 × 840 = 756,

• so 756 men were in paid work.

• (c) 18% of 840 = 0.18 × 840 = 151.2.

• But 151.2 is not a whole number. So 151 couples had a joint income of less than £160 per week. (The survey result must have been rounded, as a percentage, to the nearest whole number.)

MU120_4M3

### Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has nearly 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to university level study, find out more about the types of qualifications we offer, including our entry level Access courses and Certificates.

Not ready for University study then browse over 900 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus