# Lesson 7 Exchange Rates and Conversion graphs. Mathswatch 64.

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Lesson 7 Exchange Rates and Conversion 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 A D D B B E E C C

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 and Conversion graphs. Mathswatch 64

Why would you convert currency? Lesson 7 Exchange Rates and Conversion graphs. Mathswatch 64

What is an exchange rate? Lesson 7 Exchange Rates and Conversion 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) £50c) £135 £100 x 43.56 Baht = 4356 Baht 435.60 Baht2178 Baht 5880.60 Baht Lesson 7 Exchange Rates and Conversion graphs. Mathswatch 64 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 Bahtb) 1400 Bahtc) 70 Baht 1000 Baht ÷ 43.56 = £22.95684114 = £22.96 £4.59£32.14 £1.61 Lesson 7 Exchange Rates and Conversion graphs. Mathswatch 64 ÷ 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 = 252.50252.50 ÷ 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 gallon 3.15 ÷ 3.79 = \$0.83 per litre So we see that petrol is cheaper in the US Lesson 7 Exchange Rates and Conversion graphs. Mathswatch 64

EXAMPLES 1)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 137 litres 88 gallons 137 litres 88 gallons Lesson 7 Exchange Rates and Conversion 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 and Conversion 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 and Conversion graphs. Mathswatch 64