A house increases by 25% to £80,000. Find what it was worth before the rise.
A 15% increase means that the £80,000 represents 115% of the original value.
Therefore what we do is:
£80,000=£125% divided by 125
which gives us
£640 = 1%
then we want to multiply by 100 to change this to what we get for 100%, which gets us to:
£64,000!
So the orginal price was £64,000.
We can check that this answer makes sense: we know that there is an increase so it makes sense to get an original value less than the increased value!
(Note: I like to illustate this method with the use of a diagram which I would be able to do on the whiteboard in session mode).
AP
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