Question

Find the percentage change in the cost of an article which first increased by 20% and then decreases by 8 %.

Answer 1

Answer:

change in percentage =92%

hope it will help you

Answer 2

Question

1. Find the percentage change in the cost of an article which first increases by 20% and then decreases by 8%

Required answer:-

• 10.40% is the answer required

Solution

$\sf{Let \: the \: original \: cost \: of \: the \: article \: be \: Rs.100}$

$\sf{ After \: an \: increase \: of 20 \% \: , it \: becomes = Rs100+20 \% \: of \: Rs100}\\ \\\sf{= Rs100+Rs20=Rs120}$

Since, now it is decreased by 8%

  ⁂ Value of the article after a decrease of 8%

                                                       = Rs.120 - 8% of Rs.120

                                                       = Rs.120 - Rs.9.60 = Rs.110.40

⁂ Change (increase) on the whole

                        = final value - Initial value

                           = Rs.110.40 - Rs.100 = Rs.10.40

⁂ Percentage change (increase) = 10.4%

Alternative method :-

Since, the cost of the article was first increased by 20% and then decreased by 8%

⇒ If initial value of the articles is Rs.100

      $\sf{its \: final \: value = Rs.100 \times [ 1+ \dfrac{20}{100}] \: [1- \dfrac{8}{100}]$

                        $\sf{ => 100 \times \dfrac{120}{100} \times \dfrac{92}{100} = Rs.110.40$

⁂ Percentage change (increase) = ( Rs.110.40 - Rs.100)% = 10.40%