Question

Advanced question. Who can figure out how you can take an exchange rate which pegs $1.00 US to $1.21 CAD to see how much you would get in $US for $1.00 Cdn? It will be less than $1.00.

Answer 1

the answer is 0.83. explication

Answer 2

$0.83 when solved for (when the actual conversion is done it comes out to be $0.82)

Explanation:

We are stating that 1 US = 1.21 CAD

Since they are equal we can assume:
`(1 US)/(1.21 CAD) =1`

Assume the number we are looking for is x. x US = 1 CAD.

Since they are equal we can assume:
`(x US)/(1 CAD) =1`

Both equations are equal to 1, meaning the equations are equal to each other. So,
`(1US)/(1.21CAD)=1= (xUS)/(1 CAD)` ⇒⇒⇒⇒
`(1US)/(1.21CAD)= (xUS)/(1 CAD)`

Using cross multiplication we get
`1US*1CAD=1.21CAD*xUS`

We can discard the units (we only needed them to differentiate which currency we were talking about) to get 1 = 1.21x

Solving for x we get x = 1/1.21 = 0.82645

If you wish to round this you would get around 0.83, which is remarkably close to the actual price of 0.82. The reason for difference is in the numbers we use. When we divide 1/1.12131, we get 0.82433, which would round to be 0.82.

Hope this is correct and helps!