'e' increased by 20% is equal to 'f' increased by 50% show that e = 1.25f

Question

The actual question says "'e' increased by 20% is equal to 'f' increased by 50% show that f = 1.25e" however my teacher says that's wrong. I have no idea how to do this.

Answer 1

Which is it?  Show that e = 1.25 f, or f = 1.25 e?  Those are different.

 

So let's write out what the question says as an equation and see what is correct.

 

'e' increased by 20% -- That means, add an additional 20% of e onto e.  20% is the same as .2, so that means you get e + .2e which is equal to 1.2e

 

is equal to -- That's easy, that's just "="

 

'f' increased by 50% -- Same as above, that means 0.5f + f = 1.5f

 

So now we have 1.2e = 1.5f

 

Now divide both sides by 1.2...

 

1.2e = 1.5f

1.2 e / 1.2 = 1.5 f / 1.2

e = 1.25 f