Question

A number is reduced to 210 by a reduction of
30%. By what percent should it be increased to
convert it into 450 ?​

Answer 1

Answer:

50%

Step-by-step explanation:

Let the inital number be x.

So 30% reduction of x gives 210.

ie, (100% - 30%) *x = 70% * x = 210

so x = 210/0.7 = 300

Now the absolute increase needed to reach 450 from 300 is 450-300 = 150.

so 150/300 = 0.5

So there must be 50% increase in the initial number to  get 450.