A fraction can be seen as *a division waiting to happen*: for example, `frac(1)(4)` of a pizza means a whole pizza split, or divided, into four equal slices.

When a fraction of an amount is required, the fraction acts as an *operator* or *function* on the amount. The original amount is multiplied by the numerator and divided by the denominator. Note that the multiplication and division can be calculated in either order.

When using a mixed fraction as a multiplier, turn the mixed fraction into an improper fraction first.

Three quarters of the passengers at a train station are waiting for a train to Birmingham. If there are 120 passengers at the station, how many are waiting for the train to Birmingham?

120 x `frac(3)(4)`

= 120 x 3 ÷ 4

= 360 ÷ 4

= 90

Answer: 90

After a flood in the stock room, `frac(3)(8)` of the boxes of chocolates were found to be damaged. If there were originally 400 boxes of chocolates, how many were damaged?

`frac(3)(8)` x 400

= 3 x 50 (Divide 400 ÷ 8 = 50)

= 150

Answer: 150

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