When a quantity is
increasing or decreasing
over a period of time, we
usually use multipliers to
work out the percentage
change.
Example:
A boat was bought for £13700. During the first year, it
depreciated (decreased) in value by 15%, the second
year by 10% and the third year by 8%. Work out the
value of the boat at the end of the third year.
A decrease of 15% is a multiplier of 0.85
A decrease of 10% is a multiplier of 0.9
A decrease of 8% is a multiplier of 0.92
The value of the boat is 13700 x 0.85 x 0.9 x 0.92