A number is increased by 20% and then again by 20%. By what per cent s

1.	A number is increased by 20% and then again by 20%. By what per cent should the increased number be reduced so as to get back the original number ?
Answer» Let the original number be 100. An increase of 20% followed by another increase of 20% = \(\frac{120}{100}\) x \(\frac{120}{100}\) x 100 = 144 \(\therefore\) Required decrease = 44 Required % decrease = \(\frac{44}{144}\) x 100% = \(\frac{275}{9}\)% = 30\(\frac{5}{9}\)%

A number is increased by 20% and then again by 20%. By what per cent should the increased number be reduced so as to get back the original number ?

Answer»

Let the original number be 100.

An increase of 20% followed by another increase of 20%

= \(\frac{120}{100}\) x \(\frac{120}{100}\) x 100 = 144

\(\therefore\) Required decrease = 44

Required % decrease = \(\frac{44}{144}\) x 100% = \(\frac{275}{9}\)% = 30\(\frac{5}{9}\)%