Question

If 140 is reduced to 12 what per cent is the reduction

Answer 1

Here reduction is 140 - 12 = 128
When taking percents, remember, the referece is always the old value.
Percent reduction is then (128/140)*100 = 91.42 %

Answer 2

12/140*100=8% or 85% or 9%

100-answer = 91%