Someone else on Brainly had the same question, he showed the work so I copied it so you can see it.
We have 48 meters.
We need to increase it by 20%.
That means we have 48 and then we increase it by 20%.
That can be expressed as:
48 + (48 * 20%)
Now, another way to write that would be:
48 * 120%
Now, 120% is nothing but 120/100. This can even be simplified to 1.2.
48 * 120%
= 48 * 1.2
= 57.6
48m increased by 20% is 57.6m.
