You need to know about the idea of reciprocal numbers. Reciprocal numbers are numbers that multiplied together to get 1 which is also called inverse. This means one number will be itself, and it's reciprocal will be the denominator of a fraction that has 1 as the numerator
If you come across question like [the reciprocal of a] = 1/a
Since 1/5 is the reciprocal of 5, and they are multiplied together to get 1. This will be the inverse property of multiplication.
