model 2 net increase or decrease in % Section-Wise Topic Notes With Detailed Explanation And Example Questions

Question : 1

A number is first decreased by 20%. The decreased number is then increased by 20%. The resulting number is less than the original number by 20. Then the original number is

a) 400

b) 600

c) 500

d) 200

Question : 2

The sum of two numbers is 520. If the bigger number is decreased by 4% and the smaller number is increased by 12%, then the numbers obtained are equal. The smaller number is

a) 210

b) 300

c) 240

d) 280

Question : 3

The strength of a school increases and decreases in every alternate year by 10%. It started with increase in 2000. Then the strength of the school in 2003 as compared to that in 2000 was

a) decreased by 8.9%

b) decreased by 9.8%

c) increased by 9.8%

d) increased by 8.9%

Question : 4

Two successive price increases of 10% and 10% of an article are equivalent to a single price increase of

a) 20%

b) 22%

c) 21%

d) 19%

Question : 5

If price of a book is first decreased by 25% and then increased by 20%, the net change in the price of the book will be

a) 5% decrease

b) 5% increase

c) no change

d) 10% decrease

Question : 6

A number is increased by 10% and then it is decreased by 10%. The net change in the number is

a) 2% decrease

b) 1% decrease

c) 1% increase

d) no increase or decrease