Question

Before adding or subtracting two fractions they are converted into like fractions. Explain with examples why this is necessary.

Answer 1

Take for example (1/4)-(1/5). The way it is written, we cannot do anything with it. So when you add or subtract fractions you need to find a common denominator. In this case the common denominator is 20. 20 is the smallest number both 4 and 5 will divide into. So if the common denominator is 20, 5 times 4 gives you 20 so you multiply both the numerator and denominate by 5 to get (5/20). You do the same process to (1/5) and get (4/20). Now we can subtract because they are like fractions with the same denominator. Kind of a process that just needs to be followed. Hope it helps to some extent.