Percentages - FS self study lesson/quiz wc. 11/01/2021

Percentages - Functional Skills

Self study lesson/quiz

wc. 11/01/2021

Percentages - revision

Finding Percentage of the amount:
- 50% - half of the number (divide the number by 2)
-25% - a quarter of the number; $\frac{1}{4}$   ; (divide the number by 4)

-10% -  $\frac{1}{10}$  of the number (divide the number by 10)
- 5% - half of 10%; find 10% ie. divide the number by 10; and then half the number (divide by 2) to find 5%
- 75% - find 50% and 25% of the number; add the together
- 30% - find 10% of the number and multiply it by 3
- 15% - find 10% and 5% of the number and add them together

Percentages - revision

Finding decrease of the amount by %

eg. 20% off 70

1) Find 10 % of the num per:

70 ÷ 10 = 7

2) multiply by 2 to find 20%:

7 x 2 = 14

So 20% of 70 is 14

3) Take 20% away from 70:

70 - 14 = 56

Answer: 20% off 70 is 56

Multiple Choice

1. Find 40% of 68 kg

• 6.8 kg

• 13.6 kg

• 27.2 kg

• 30 kg

Find 40% of 68kg

1) Find 10% of 68:

68 ÷ 10 = 6.8

2) multiply 10% by 4 to find 40%:

6.8 x 4 = 27.2

Answer: 40% of 68 kg is 27.2 kg

What is 50% of 124?

124 ÷ 2 = 62

Multiple Choice

3. What is 25% of 96?

• 22

• 24

• 23

• 30

What is 25% of 96?

96 ÷ 4 = 24

So 25% of 96 is 24

Multiple Choice

4. What is 25% of 24.80?

• 12

• 6.8

• 9.2

• 6.2

What is 25% of 24.80?

24.80 ÷ 4 = 6.2

So 25% of 24.8 is 6.2

Multiple Choice

5. How to find 10% of the number?

• multiply by 10

• divide by 10

• half the number and then half it again

• divide by 2

How to find 10% of the number?

100% ÷ 10 = 10%

Therefore, to find 10% of the number we need to divide by 10!

What is 10% of 2460?

2460 ÷ 10 = 246

So 10% of 2460 is 246

Multiple Choice

7. What is 15% of 160?

• 24

• 16

• 32

• 8

What is 15% of 160?

1) find 10% of the number:

160 ÷ 10 = 16

2) Find 5% of the number (5 % is 10% ÷ 2):

16 ÷ 2 = 8

3) Add 10% and 5%:

16 + 8 = 21

15% of 160 is 21

A holiday costs £1870. The travel agent asks for 25% deposit. How much is deposit?

25% is a quarter ( $\frac{1}{4}$  ) of the number:

1870 ÷ 4 = 467.50

Therefore, the deposit is £467.50

A coat priced at £120 is reduced by 50% in a sale. What is the coat price after the reduction?

50% of £120 is £60.

Therefor the coat price after the reduction is £60.

(£120 - £60 = £60)

Multiple Choice

10. A deposit of 30% has been paid on a holiday costing £1040. How much is there left to pay?

• £312

• £628

• £712

• £728

A deposit of 30% has been paid on a holiday costing £1040. How much is there left to pay?

1) Find 10%

1040 ÷ 10 = 104

2) Multiply this by 3 to find 30%:

104 x 3 = 312

That means that £312 has been already paid and the remaining amount can be found if we take it away from the cost of holiday.

3) £1040 - £312 = £728

Answer: There is £728 left to pay

Poll

Can you find 50%, 25% and 10% of the number?

• 1) I understand very well

• 2) I need more practice

• 3) I don’t understand

Poll

Can you find 5%, 25%, 30%, 75% (multiples of 5 and 10) of the number?

• 1) I understand it very well

• 2) I need more practice

• 3) I don't understand

Poll

Can you find decrease fo the number by a % (eg. price drop due to a sale in the shop)?

• 1) I understand it very well

• 2) I need more practice

• 3) I don't understand

Percentages

- Check resources on MOODLE, if you need to revise % a little more

- Remember to work on BKSB for 20 minutes today;

Have a good day :-)