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Page 1 1. What percent of (i) 24 is 6? (ii) Rs 125 is Rs 10? (iii) 4km is 160 meters? (iv) Rs 8 is 25 paise? (v) 2 days is 8 hours? (vi) 1 liter is 175ml? Solution: (i) According to the question required percentage = (6/24) × 100 = (100/4) = 25% (ii) According to the question required percentage = (10/125) × 100 = (1000/125) = 8% (iii) According to the question required percentage = (160/4) × 100 We know that 1km = 1000 meters Therefore 4km = 4000 meters = (160/4000) × 100 = 4% (iv) According to the question required percentage = (25/8) × 100 We know that 1Rs = 100 paise Therefore 8Rs = 800 paise = (25/800) × 100 = (25/8) = 3.125% (v) We know that 1day = 24 hours 1 hour = (1/24) day 8 hours = (8/24) day = (1/3) day According to the question required percentage = [(1/3)/2] × 100 Page 2 1. What percent of (i) 24 is 6? (ii) Rs 125 is Rs 10? (iii) 4km is 160 meters? (iv) Rs 8 is 25 paise? (v) 2 days is 8 hours? (vi) 1 liter is 175ml? Solution: (i) According to the question required percentage = (6/24) × 100 = (100/4) = 25% (ii) According to the question required percentage = (10/125) × 100 = (1000/125) = 8% (iii) According to the question required percentage = (160/4) × 100 We know that 1km = 1000 meters Therefore 4km = 4000 meters = (160/4000) × 100 = 4% (iv) According to the question required percentage = (25/8) × 100 We know that 1Rs = 100 paise Therefore 8Rs = 800 paise = (25/800) × 100 = (25/8) = 3.125% (v) We know that 1day = 24 hours 1 hour = (1/24) day 8 hours = (8/24) day = (1/3) day According to the question required percentage = [(1/3)/2] × 100 = 100/6 = 16 2/3 % (vi) We know that 1liter = 1000ml According to the question required percentage = (175/1000) × 100 = 17500/1000 = 17.50 % 2. What percent is equivalent to (3/8)? Solution: Given (3/8) = (3/8) × 100 = 37.5% 3. Find the following: (i) 8 is 4% of which number? (ii) 6 is 60% of which number? (iii) 6 is 30% of which number? (iv) 12 is 25% of which number? Solution: (i) Let x be the required number Given that 4% of x = 8 (4/100) × x = 8 x = (800/4) x = 200 (ii) Let the required number be x Given that 60% of x = 6 (60/100) × x = 6 x = (60/6) x = 10 (iii) Let the required number be x Given that 30% of x = 6 (30/100) × x = 6 Page 3 1. What percent of (i) 24 is 6? (ii) Rs 125 is Rs 10? (iii) 4km is 160 meters? (iv) Rs 8 is 25 paise? (v) 2 days is 8 hours? (vi) 1 liter is 175ml? Solution: (i) According to the question required percentage = (6/24) × 100 = (100/4) = 25% (ii) According to the question required percentage = (10/125) × 100 = (1000/125) = 8% (iii) According to the question required percentage = (160/4) × 100 We know that 1km = 1000 meters Therefore 4km = 4000 meters = (160/4000) × 100 = 4% (iv) According to the question required percentage = (25/8) × 100 We know that 1Rs = 100 paise Therefore 8Rs = 800 paise = (25/800) × 100 = (25/8) = 3.125% (v) We know that 1day = 24 hours 1 hour = (1/24) day 8 hours = (8/24) day = (1/3) day According to the question required percentage = [(1/3)/2] × 100 = 100/6 = 16 2/3 % (vi) We know that 1liter = 1000ml According to the question required percentage = (175/1000) × 100 = 17500/1000 = 17.50 % 2. What percent is equivalent to (3/8)? Solution: Given (3/8) = (3/8) × 100 = 37.5% 3. Find the following: (i) 8 is 4% of which number? (ii) 6 is 60% of which number? (iii) 6 is 30% of which number? (iv) 12 is 25% of which number? Solution: (i) Let x be the required number Given that 4% of x = 8 (4/100) × x = 8 x = (800/4) x = 200 (ii) Let the required number be x Given that 60% of x = 6 (60/100) × x = 6 x = (60/6) x = 10 (iii) Let the required number be x Given that 30% of x = 6 (30/100) × x = 6 x = (6 × 100)/30 x = 20 (iv) Let the required number be x Given that 25% of x = 12 (25/100) × x = 12 x = (12 × 100)/25 x = 48 4. Convert each of the following pairs into percentages and find out which is more? (i) 25 marks out of 30, 35 marks out of 40 (ii) 100 runs scored off 110 balls, 50 runs scored off 55 balls Solution: (i) Given 25 marks out of 30 Consider 25 marks out of 30 = (25/30) × 100 = (250/3) = 83.33% Also given that 35 marks out of 40 Now consider 35 marks out of 40 = (35/40) × 100 = 87.5% Clearly 87.5 > 83.33 After converting into percentage 35 marks out of 40 = 87.5% is more (ii) Given 100 runs scored off 110 balls Consider 100 runs scored off 110 balls = (100/110) × 100 = 90.91% Also given that 50 runs scored off 55 balls Consider 50 runs scored off 55 balls = (50/55) × 100 = 90.91% Here both are equal 5. Find 20% more than Rs.200. Solution: Consider 20% of 200 = (20/100) × 200 = Rs 40 Page 4 1. What percent of (i) 24 is 6? (ii) Rs 125 is Rs 10? (iii) 4km is 160 meters? (iv) Rs 8 is 25 paise? (v) 2 days is 8 hours? (vi) 1 liter is 175ml? Solution: (i) According to the question required percentage = (6/24) × 100 = (100/4) = 25% (ii) According to the question required percentage = (10/125) × 100 = (1000/125) = 8% (iii) According to the question required percentage = (160/4) × 100 We know that 1km = 1000 meters Therefore 4km = 4000 meters = (160/4000) × 100 = 4% (iv) According to the question required percentage = (25/8) × 100 We know that 1Rs = 100 paise Therefore 8Rs = 800 paise = (25/800) × 100 = (25/8) = 3.125% (v) We know that 1day = 24 hours 1 hour = (1/24) day 8 hours = (8/24) day = (1/3) day According to the question required percentage = [(1/3)/2] × 100 = 100/6 = 16 2/3 % (vi) We know that 1liter = 1000ml According to the question required percentage = (175/1000) × 100 = 17500/1000 = 17.50 % 2. What percent is equivalent to (3/8)? Solution: Given (3/8) = (3/8) × 100 = 37.5% 3. Find the following: (i) 8 is 4% of which number? (ii) 6 is 60% of which number? (iii) 6 is 30% of which number? (iv) 12 is 25% of which number? Solution: (i) Let x be the required number Given that 4% of x = 8 (4/100) × x = 8 x = (800/4) x = 200 (ii) Let the required number be x Given that 60% of x = 6 (60/100) × x = 6 x = (60/6) x = 10 (iii) Let the required number be x Given that 30% of x = 6 (30/100) × x = 6 x = (6 × 100)/30 x = 20 (iv) Let the required number be x Given that 25% of x = 12 (25/100) × x = 12 x = (12 × 100)/25 x = 48 4. Convert each of the following pairs into percentages and find out which is more? (i) 25 marks out of 30, 35 marks out of 40 (ii) 100 runs scored off 110 balls, 50 runs scored off 55 balls Solution: (i) Given 25 marks out of 30 Consider 25 marks out of 30 = (25/30) × 100 = (250/3) = 83.33% Also given that 35 marks out of 40 Now consider 35 marks out of 40 = (35/40) × 100 = 87.5% Clearly 87.5 > 83.33 After converting into percentage 35 marks out of 40 = 87.5% is more (ii) Given 100 runs scored off 110 balls Consider 100 runs scored off 110 balls = (100/110) × 100 = 90.91% Also given that 50 runs scored off 55 balls Consider 50 runs scored off 55 balls = (50/55) × 100 = 90.91% Here both are equal 5. Find 20% more than Rs.200. Solution: Consider 20% of 200 = (20/100) × 200 = Rs 40 Therefore 20% more than Rs 200 = 200 + 40 = Rs 240 6. Find 10% less than Rs.150 Solution: Consider 10% of 150 = (10/100) × 150 = Rs 15 Therefore 10% less than Rs 150 = 150 - 15 = Rs 135Read More
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