Question

A number is first increased by 20% and the resulting number is then decreased by 10%. Find the overall change in the number as percent.​

Answer 1

→Answer :

Let the original number = 100

Let the original number = 100Increased by 20%

Let the original number = 100Increased by 20%∴ New number = 100 + 20 = 120

Let the original number = 100Increased by 20%∴ New number = 100 + 20 = 120Decreased by 10% = (120 × 10)/100 = 12

Let the original number = 100Increased by 20%∴ New number = 100 + 20 = 120Decreased by 10% = (120 × 10)/100 = 12∴ New number = 120 – 12 = 108

Let the original number = 100Increased by 20%∴ New number = 100 + 20 = 120Decreased by 10% = (120 × 10)/100 = 12∴ New number = 120 – 12 = 108Overall change = 108 – 100 = 8

Let the original number = 100Increased by 20%∴ New number = 100 + 20 = 120Decreased by 10% = (120 × 10)/100 = 12∴ New number = 120 – 12 = 108Overall change = 108 – 100 = 8Reqd. percentage = 8/100 × 100 = 8% (increased

Answer 2

Answer:

x-100%

Step-by-step explanation:

let the no. be x

x+20%

= x+20/100

=x+1/5

x+1/5-1/10

=x+1/5-10/100

=x+1/5-1/10

=5x+1/5-1/10

=10x-1/10