Problem : 1 [ Percentage ]       Solve this type of problem 1. A number is 20 % of 80 .   Show Answer A: `20` % of `80 = 20 / 100 × 80 = 16`.

Problem : 2 [ Percentage ]       Solve this type of problem 2. 42 is 3 % of some number.   Show Answer A: Let `42` is `3` % of X `3 / 100 × X = 42` `=> X = 42 × 100/3` `=> X = 1400` .

Problem : 3 [ Percentage ]       Solve this type of problem 3. What percent of 65 is 130 .   Show Answer A: Let X % of `65` is `130` `=> X/100 × 65 = 130` `=> X = (130 × 100 )/65` `=> X = 200` %

Problem : 4 [ Percentage ]       Solve this type of problem 4. A's annual income is increased/decreased from Rs 60000 to Rs 75000 . Find the percentage of increase in A's income.   Show Answer A: A's original income = Rs `60000` A's new income = Rs `75000` `=>` Increase = Rs `15000` `=>` Increase % = `("Increase")/"Original Income" × 100 = 15000 / 60000 × 100 = 25` A's income is increased by `25` %

Problem : 5 [ Percentage ]       Solve this type of problem 5. In a school of 225 boys, 15 were absent then what percent were present ?   Show Answer A: In a school of `225` boys, `15` were absent `:. 225 - 15 = 210` were present `:.` present % = `210 / 225 × 100 = 93.3333` %

Problem : 6 [ Percentage ]       Solve this type of problem 6. A earns 25 % more than B. By what percent does B earn less then A.   Show Answer A: Let A's income = Rs `100` `:.` B's income = Rs `( 100 + 25 )` = Rs `125` B's Income Rs A's Income Rs 125 100 100 ? A's Income = `( 100 × 100 ) / 125 = 80` Rs `:.` A's income is Rs `20` less than by B's income (Rs `100`) `:.` A's income is `20` % less than by B's income.

Problem : 7 [ Percentage ]       Solve this type of problem 7. A reduction of 20 % in the price of basmati rice would enable a man to buy 2 kg of rice more for Rs 250 . Find the reduced price per kg.   Show Answer A: A reduction of `20` % in the price of basmati rice would enable a man to buy `2` kg of rice more for Rs `250` . `:.` Reduced price of `2` kg rice = `20` % of Rs `250 = 20 / 100 × 250 = 50` `:.` Reduced price of `2` kg rice = Rs `50` `:.` Reduced price of per kg rice = Rs `25`

Problem : 8 [ Percentage ]       Solve this type of problem 8. The price of tea has gone up by 20 %. By how much percent should its consumption be reduced so as not to increase the expenditure?   Show Answer A: Let price of tea be Rs `100` per kg `:.` new price of tea = Rs `( 100 + 20 )` = Rs `120` per kg Now not to increase the expenditure, its consumption must be reduced by Rs `20` New Price Rs Reduced Consumption Rs 120 20 100 ? Reduced Consumption = `(100 × 20) / 120 = 16.6667` Rs `:.` Consumption must be reduced by Rs `16.6667` , if original price of tea be Rs `100` `:.` Consumption must be reduced by `16.6667` % for not to increase the expenditure.

Problem : 9 [ Percentage ]       Solve this type of problem 9. Find the selling price of an item, of which the printed price is Rs 25000 if the successive discounts given are 10 %, 8 % and 4 %.   Show Answer A: Here, printed price of an item = `25000` The amount paid by customer = `90` % of `92` % of `96` % of `25000` `:.` amount after discounts = `25000 × 90 / 100 × 92 / 100 × 96 / 100` `:.` amount after discounts = `19872` Hence selling price of an item is Rs `19872` .

Problem : 10 [ Percentage ]       Solve this type of problem 10. The successive discount of 10 % and 5 % are given on the purchased Computer. If the final price of the Computer is Rs 10260 , then find the printed price of the Computer.   Show Answer A: Let the printed price of computer be Rs `X` The amount paid by customer = `90` % of `95` % of `X` `:.` amount after both the discounts `= X × 90 / 100 × 95 / 100` `:. 10260 = X × 90 / 100 × 95 / 100` `:. X = (10260 × 100 × 100 ) / (90 × 95) = 12000` Hence printed price of the computer is Rs `12000`.