LESSON NOTE ON EVERYTHING YOU NEED TO KNOW ABOUT CURRENCY EXCHANGE RATES AND WHAT IT MEANS TO YOU.

Subject: Number theory.

Topic: Foreign Exchange.

Lesson: How to convert from one currency to another.

Previous knowledge: Students can solve problems using ratio and proportion

Objectives: By the end of the lesson students should be able to

_Convert from one currency to another.

_Make calculations in different currencies whose exchange rates are known.

_Google exchange using internet

Teaching Aids: Some foreign currencies, chalk, board, well arranged class, pictures of foreign notes.

Teaching Methods: Demonstration, Question, Assignment

Grade level: 7

Duration: 45minutes

Date: 12/03/2019

Introduction:

Ex, five cans of beer cost 1.20$. What is the cost of 7 cans of beer?

                                      Solution

5cans= 120$

7cans=x

 7/5 = x/120

       x = 168. So 7 cans will cost $168

Presentation?

Money is changed from one currency into another using simple proportions

                                            Exchange rates fluctuates a lot making prices unstable.

Below are some exchange rates as of February 2019

                           

Country	Rate of exchange
1 US Dollar	578frs CFA
1 crane Dollar	478frs CFA
1 Euro	650frs CFA
1 Roam	785frs CFA
1 Norn
1 Shelling

As of April 1982

Country	Rate of exchange
Belgium(Franc)	BF 8.7=1pound
France(Franc)	fr 10.9=1pound
Germany(mark)	DM 4.2=1pound
Italy(lire)	Lire2280=1pound
Spain(peseta)	Ptas 182=pound
United states(Dollar)	$1.74=pound

Example 1: If a bottle of wine cost 8 francs what is the cost in British money

                                         Solution

               10.9fr =1£

              8.0 =x

              8.0/10.9=x/£

                  8x = 0.73£

The bottle cost approximately 73 penny in British money.

            Example2: convert $500 into German marks

                     DM 4.2 =1£

                     $1.74 =1£

$1.74 =   4.2DM

$500 = x

500/1.74 = x/4.2DM

X = 500/1.74*4.2DM

=$500 = DM 1206

Example 3

a.       Change the amount of British money into the foreign currency stated

-          20 £  to (French Francs)

-          70£ to  (Dollars)

-          200£ to (pesetas)

-          230£ to(Lire)

-          90£ to(Dollars)

                         Solution

1)      10.9fr = 1£

X         = 20£

X/10.9 = 20£/1£

X = 20*10.9fr

So, 20£= 218Fr. Ans

2)      $1.74 = 1£

X = 7£

X/7.4 = 70p/1£

x/$1.74 = 70

So, x = 70p ($1.74)

Therefore, 70p = $121.8 ans.

 Example 4: Change the amount of foreign currency into British money

1)      Fr 500

2)      DM 7.5

3)      Lire 500,000

4)      $2500

5)      BF900

6)      Pitas 950

                  Solution

i)                    Fr  500 to pounds

10.9fr=1£

500fr=x

500/10.9fr=x/1£

X = 45.87p                                         
Therefore 500fr = 45.87£
                                                                                                                                                                              

1)       DM 7.

ii). DM 7.5

     DM 4.2 = 1£

    DM 7.5 = x

           7.5/4.2 = x/1£

7.5/4.2*1p = x

1.79p = DM7.5                                         

                 Therefore DM 7.5 = 1.79£       

       Example 5. A second handed laptop costs 4.50£ in Britain and $4.70 in USA. How much cheaper is the laptop in British money when bought in the USA?

                                  Solution

$1.74 =1£

$4.70 = x

$4.70/$1.74= x/1£

4.70/1.74 = x/1£

(4.70/1.74)1£=x

  2.70£ = x

Or x=2.70£

 Therefore $4.70= 2.70£

4.5£ -2.70£= 1.80£. The laptop will be 1.80£ cheaper when bought with British money in the USA. Living in USA is cheaper than living in Britain according to the above exchange rates.

     Example 6. A bottle of whisky costs 582 Pesetas in Spain and Fr 48 in France. Which is cheaper in British money and by how much?

                                                    Solution

In Spain,

182Ptas=1£

582Ptas=x

Using proportions

582Ptas/182Ptas= x/1£

582/182=x/1£

(582/182)1£=x

X= 3.20£

Therefore 582Ptas= 3.20£

In France,

10.9Fr =1£

48Fr=x

48Fr/10.9Fr=x/1£

(48/10.9)1£=x

x=4.40£

Therefore 48Fr=4.40£

From above, the whisky is cheaper in Spain than in France by (4.40£-3.20£)= 1.20£

If you are businessman, it will be better to buy this whisky from Spain than France.

EVALUATION

1 )Change the amount of money into the foreign currency stated beside each

i)                    £200 to Pesetas ,  ii) £2.3 to Lire

Solution

i)                    £200 to Pesetas

£1 = 182Ptas

 £200= y

£200/£1=y/182Ptas

Y= 200×182Ptas

Y=36400Ptas. Answer.

ii)                   £1= 2280lire

£2.3=x

£2.3/£1=x/2280lire

(2.3/1) 2280lire=x

5224lire=x

Therefore £2.3=5224lire.

2) Change each of the following foreign currencies into British money

    i) BF 900, ii) $2500, iii) 950 Pesetas.

                         Solution

i)                    8.7BF = £1

900BF = y

900BF/8.7BF=y/£1

y=(900/8.7)×£1

y=103.45£

ii)                   $1.74=£1

$2500=x

$2500/$1.74=x/£1

(2500/1.74)×£1=x

£1436.78=x

Therefore $2500=£1436.78 answer.

iii)                 182Ptas= £1

950Ptas=x

950Ptas/182Ptas=x/£1

(950/182)£1=x

£5.22=x

Therefore, 950Ptas= £5.22 Answer.

3) Jaguar XJS is sold in several countries at prices given below:

         Britain= £15,000

         Belgium=BF, 1,496,400

          France = Fr, 194,020

          Germany=DM, 52,080

          USA= $ 24,882.

Write out in order a list of the prices converted in pounds.

4) A traveler in Switzerland exchanges 1300 Swiss Francs for £1400. What is the exchange rate?. ($1=3.25 Swiss Fr).

                                             Solution

                                         $400=1300SF

                                              $1=x

                                        $1/$400=x/1300SF

                                             (1/400)=x/1300SF

                                            (1/400)×1300SF=x

                                               3.25SF =x

                                         Therefore $1=3.25SF. The exchange rate.

    

5) An Irish gentleman on holiday in Germany finds that his wallet contains $1700. If he changes the money in the bank, how much Dutch Marks will he receive?

                                                  SOLUTION

                     Convert $1700 to £ and from £ to Dutch Marks (DM)

                          $1.74=£1

                          $1700=k

                         $1700/$1.74=k/£1

                           (1700/1.74)×£1=k

                                  K=£977.01

                  $1700=£977.01

                   £1=4.2DM

                £977.01=n

                 £977.01/£1=n/4.2DM

                     (977.01/1)×4.2DM=n

                       4103.44DM=n

 Hence, 4103.44DM=£977.01=$1700

Therefore he will receive 4103.44DM from $1700.

6)      An English Soccer Fan is arrested and has to pay a fine of 2000French Francs. He has 10,000 German marks in his wallet. How much has he left in British money after paying the fine.

                                         Solution

As above, convert the 2000Ff to Pounds (£) then to German marks.

                 10.9Fr= £1

                2000Fr=x₁

               2000Fr/10.9Fr=x/£1

              (2000/10.9)×£1=x₁

                  £183.49=x₁

                  2000Fr=£183.49

                     £1=4.2DM

               £183.49=x₂

                         £183.49/£1=x₂/4.2DM

                      (183.49/1)×4.2DM=x₂

                        770.66DM=x₂

                         2000Fr= 770.66DM

Change 10,000DM to £

Change the 2000Fr to £

Subtract to get the difference from above as follows:

4.2DM = £1

10,000DM= x₃

10,000DM/4.2DM=x₃/£1

(10,000/4.2)×£1 =x₃

X₃=£2380.95

Therefore 10,000DM= £2380.95

Money left after payment of fine=£2380.95-£183.49

Money left=£2197.46. Answer

SUMMARY

Ø  Study the table of exchange rates above and apply them. For recent exchange rates, search in Google and apply the knowledge of proportion to calculate exchanges.

Ø  To calculate exchange rates, ensure that the currencies are in the same unit

a knowledge of exchange rates will guide you on the following:

>when and where to do business.

>where to study at cheaper rate.

>Which foreign country to settle in.

>Where to buy goods that can be sold and make more profit. 

CONCLUSION

Exercise

1)      The cost of a second hand Renault truck was estimated to be costing Fr 218000. How much is this in pounds.

2)      A jet plane costs £1496,500. How much will same jet cost if bought in USA.
               Watch this   https://youtu.be/G5zpDAzYNzM if yo did not see it before now.