Lesson 7 Exchange Rates andConversion graphs.

Mathswatch 64

GCSE Maths Starter 7

2. Expand x(x + 3)3. Evaluate 32.9 x 17 (no calc)4. Increase $72 by 15% (no calc)

5. Which of the shapes below are congruent?

1) Find the median and range of the stem and leaf below.

A

D

B

EC

• To interpret conversion graphs.• To calculate the conversion between two

types of units.• To solve problems involving conversions.EXTN: To establish best value using conversion of units. (Grade C)

Lesson 7 Exchange Rates andConversion graphs.

Mathswatch 64

Why would you convert currency?

Lesson 7 Exchange Rates andConversion graphs.

Mathswatch 64

What is an exchange rate?

Lesson 7 Exchange Rates andConversion graphs.

Mathswatch 64

I know £1 = ฿43.56 (Thai Baht) what would I do to find how much £100 is?

So to convert between £ and ฿ you need to x 43.56

X 43.56

£1 = ฿43.56

Convert the following amounts to Thai Baht.a) £10 b) £50 c) £135

£100 x 43.56 Baht = 4356 Baht

435.60 Baht 2178 Baht 5880.60 Baht

Lesson 7 Exchange Rates andConversion graphs.

Mathswatch 64

X 43.56 X 43.56 X 43.56

I know £1 = ฿43.56 (Thai Baht) how would I work out how many pounds, 1000 Baht is?

So to convert between £ and ฿ you need to ÷ 43.56

÷ 43.56

£1 = ฿43.56

Convert the following amounts to British Pounds (GBP).a) 200 Baht b) 1400 Baht c) 70 Baht

1000 Baht ÷ 43.56 = £22.95684114= £22.96

£4.59 £32.14 £1.61

Lesson 7 Exchange Rates andConversion graphs.

Mathswatch 64

÷ 43.56 ÷ 43.56 ÷ 43.56

New York, USA £1 = $1.51 I now take my family to New York. I

convert £350 to US Dollars. a) Calculate how many US dollars I

have?

b) I spend $276 on my visit to New York and return to England. I convert my remaining money to Pounds. Calculate the remaining to GPB (£)?

350 x 1.51 = $528.50

$528.50 - $276 = 252.50 252.50 ÷ 1.51 = £167.22

Sydney, Australia £1 = $1.45 I now take my family to Sydney. I

convert £1200 to Australian Dollars.a) Convert £1200 to Aussie Dollars?

b) I spend $1476 Dollars whilst in Sydney. I convert the remaining currency back to Pounds. How many pounds and pence do I have?

1200 x 1.45 = $1740

$1740 - $1476 = $ 264 $264 ÷ 1.45 = £182.07

In the UK, petrol cost £1.24 per litre. In the USA, petrol cost 3.15 dollars per US

gallon.

1 US Gallon = 3.79 Litres£1 = $1.51

UK or USA? Show why?

In the UK petrol is £1.24 per litre.1.24 x 1.51 = $1.87 per litre (convert to US dollars)

In the US Petrol is $3.15 per gallon3.15 ÷ 3.79 = $0.83 per litre

So we see that petrol is cheaper in the US

Lesson 7 Exchange Rates andConversion graphs.

Mathswatch 64

EXAMPLES1) 2)

Use the conversion graph to convert:(a) 70 kg to pounds(b) 120 pounds to kg

Use the conversion graph to convert:(a) 30 gallons to litres(b) 400 litres to gallons

154 lbs

154 pounds

54 kg

54 kg

137 litres

88 gallons

137 litres88 gallons

Lesson 7 Exchange Rates andConversion graphs.

Mathswatch 64

1)

10cm

23cm

2in

8.75in

2.5cm

Read off the value for 9in (23cm) and multiply this by 2 (46cm)

Lesson 7 Exchange Rates andConversion graphs.

Mathswatch 64

Lesson 7 Exchange Rates andConversion graphs.

Mathswatch 64

• To interpret conversion graphs.• To calculate the conversion between two

types of units.• To solve problems involving conversions.EXTN: To establish best value using conversion of units. (Grade C)

Lesson 7 Exchange Rates andConversion graphs.

Mathswatch 64