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NCERT Solutions for Class 7 Maths Chapter 2 Fractions and Decimals Exercise 2.1Ex 2.1 Class 7 Maths Question 1.Solve:Solution:

Ex 2.1 Class 7 Maths Question 2.Arrange the following in descending order:(i) 29 , 23 ,Solution:821(ii) 15 , 37 ,710Ex 2.1 Class 7 Maths Question 3.In a “magic square” the sum of number in each row, in each column and along the diagonals is the same. Is this a magic square?Solution:

Since, the sum of all the fraction row wise, column wise and the diagonal wise is same i.e. 15 .11Hence, it is a magic square.Ex 2.1 Class 7 Maths Question 4.A rectangular sheet of paper is 12 1 cm long and 10 2 cm wide. Find its perimeter.23Solution:Ex 2.1 Class 7 Maths Question 5.Find the perimeter of (i) ABE (ii) the rectangle BCDE in this figure. Whose perimeter is greater?Solution:(i) Perimeter of ABE

Thus perimeter of ABE is greater than the perimeter of the rectangle BCDE.Ex 2.1 Class 7 Maths Question 6.Salil wants to put a picture in a frame. The picture is 7 3 cm wide. To fit in the frame, the picture cannot be more than5How much should the picture be trimmed?Solution:The width of the picture7 103cm wide.

Hence, the required width to be trimmed 3 cm.10Ex 2.1 Class 7 Maths Question 7.Ritu ate 3 part of an apple and the remaining apple was eaten by her brother Somu. How much part of the apple did Somu eat? Who5had the larger share? By how much?Solution:Let the whole part of the apple be 1.Ex 2.1 Class 7 Maths Question 8.Michael finished colouring a picture in 7 hour. Vaibhav finished colouring the same picture in 3 hour. Who worked longer? By what124fraction was it longer?Solution:Time taken by Michael 7 hour12Time taken by Vaibhav 3 hour4

NCERT Solutions for Class 7 Maths Chapter 2 Fractions and Decimals Exercise 2.2Ex 2.2 Class 7 Maths Question 1.Which of the drawings (a) to (d) show.(i)2 15(iii)3 (ii)2 23(iv)3 1214Solution:(i) 2 1 represents drawing (d)5(ii) 2 1 represents drawing (b)2(iii) 3 2 represents drawing (a)3(ic) 3 1 represents drawing (c)4Ex 2.2 Class 7 Maths Question 2.Some pictures (a) to (c) are given below. Tell which of them show:

Solution:(i) 3 1 35 represents figure (c)5(ii) 2 1 2 represents figure (a)33(iii) 3 3 2 1 represents figure (b)44Ex 2.2 Class 7 Maths Question 3.Multiply and reduce to lowest form and convert into a mixed fraction:Solution:Ex 2.2 Class 7 Maths Question 4.Shade:(i) 1 of the circles in box (a)2(ii) 2 of the circles in box (b)3(iii) 3 of the circles in box (c)5

Solution:Ex 2.2 Class 7 Maths Question 5.Find:Solution:

Ex 2.2 Class 7 Maths Question 6.Multiply and express as a mixed fraction.Solution:

Ex 2.2 Class 7 Maths Question 7.Find:Solution:Ex 2.2 Class 7 Maths Question 8.Vidya and Pratap went for a picnic. Their mother gave them a water bottle that contained 5 litres of water. Vidya consumed 2 of the5water. Pratap consumed the remaining water.(i) How much water did Vidya drink?(ii) What fraction of the total quantity of water did Pratap drink?Solution:(i) Water consumed by Vidya 2 of 5 litres5Water consumed by Patap 5 litres – 2 litres 3 litres(ii) Fraction of water consumed by Pratap 3 litres5

NCERT Solutions for Class 7 Maths Chapter 2 Fractions and Decimals Exercise 2.3Ex 2.3 Class 7 Maths Question 1.Find:Solution:Ex 2.3 Class 7 Maths Question 2.Multiply and reduce to lowest form (if possible):

Solution:Ex 2.3 Class 7 Maths Question 3.Multiply the following fractions:Solution:

Ex 2.3 Class 7 Maths Question 4.Which is greater:Solution:Ex 2.3 Class 7 Maths Question 5.Saili plants 4 saplings, in a row, in her garden. The distance between two adjacent saplings is 3 m. Find the distance between the first4and the last sapling.Solution:Number of saplings 4Distance between two adjacent saplings 3 m4 Distance between the first and the last sapling

Ex 2.3 Class 7 Maths Question 6.Lipika reads a book for 1 3 hours everyday. She reads the entire book in 6 days. How many hours in all were required by her to read the4book?Solution:In 1 day Lipika needs 1 3 hours4In 6 days Lipika will need 6 1 3 hours4Hence the required hours 10 1 .2Ex 2.3 Class 7 Maths Question 7.A car runs 16 km using 1 litre of petrol. How much distance will it cover using 2 3 litres of petrol?4Solution:In 1 litre of petrol, the car covers 16 km distance In 2 3 litres of petrol, the car will cover 2 3 16 km distance4Hence, the required distance 44 km.Ex 2.3 Class 7 Maths Question 8.Solution:4

NCERT Solutions for Class 7 Maths Chapter 2 Fractions and Decimals Exercise 2.4Ex 2.4 Class 7 Maths Question 1.Find:Solution:

Ex 2.4 Class 7 Maths Question 2.Find the reciprocal of each of the following fractions. Classify the reciprocals as proper fractions, improper fractions and whole numbers.(i) Reciprocal of 37(ii) Reciprocal of 58 73 , which is improper fraction. 85 , which is improper fraction.(iii) Reciprocal of 97 7 , which is proper fraction.9

(iv) Reciprocal of 6 56 , which is proper fraction.5(vi) Reciprocal of 12 7 , which is proper fraction.712(vi) Reciprocal of 1 8, which is whole number.8(vii) Reciprocal of 111 11, which is whole number.Ex 2.4 Class 7 Maths Question 3.Find:Solution:Ex 2.4 Class 7 Maths Question 4.Find:Solution:

NCERT Solutions for Class 7 Maths Chapter 2 Fractions and Decimals Exercise 2.5Ex 2.5 Class 7 Maths Question 1.Which is greater?(i) 0.5 or 0.05(ii) 0.7 or 0.5(iii) 7 or 0.7

(iv) 1.37 or 1.49(v) 2.03 or 2.30(vi) 0.8 or 0.88Solution:(i) 0.5 or 0.05Comparing the tenths place, we get 5 0 0.5 0.05(ii) 0.7 or 0.5Comparing the tenths place, we get 7 5 0.7 0.5(iii) 7 or 0.7Comparing the one’s place, we get 7 0 7 0.7(iv) 1.37 or 1.49Comparing the tenths place, we get 3 4 1.37 1.49 or 1.49 1.37(v) 2.03 or 2.30Comparing the tenths place, we get 0 3 2.03 2.30 or 2.30 2.03(vi) 0.8 or 0.88 0.80 or 0.88Since tenths place is same.Comparing the hundredth place, we get 0 8 0.80 0.88 or 0.88 0.80Ex 2.5 Class 7 Maths Question 2.Express as rupees using decimals:(i) 7 paise(ii) 7 rupees 7 paise(iii) 77 rupees 77 paise(iv) 50 paise(v) 235 paiseSolution:(i) Since 1 rupee 100 paise and 1 paise 1 rupees7 paise 7 rupees 0.07 rupees100100(ii) 7 rupees 7 paise 7 rupees 7 rupees100 7.07 rupees(iii) 77 rupees 77 paise 77 rupees 77 rupees100 77.77 rupees(iv) 50 paise 50 rupees 0.50 rupees100(v) 235 paise 235 rupees 2.35 rupees100Ex 2.5 Class 7 Maths Question 3.(i) Express 5 cm in metre and kilometre(ii) Express 35 mm in cm, m and km.Solution:(i) 1 metre 100 cm1 kilometre 1000 metre 100 1000 cm 100000 cm 5 cm 5 metre 0.05 metre10055 cm km 0.00005 km100000Hence, 5 cm 0.05 m and 0.00005 km(ii) 1 cm 10 mm and 1 km 100000 cm 35 mm 35 cm 3.5 cm,1035 mm 35 m 0.035 m10003535 mm km 0.000035 km1000000Hence, 35 mm 3.5 cm, 0.035 m and 0.000035 km.

Ex 2.5 Class 7 Maths Question 4.Express in kg:(i) 200 g(ii) 3470 g(iii) 4 kg 8 gSolution:(i) 200g 200 kg [ 1 kg 1000g]1000 0.2 kg(ii) 3470 g 3470 3.47 kg [ 1 kg 1000 g]10000(iii) 4 kg 8 g 4 kg 8 kg [ 1 kg 1000 g]10000 4 kg 0.008 kg 4.008 kgEx 2.5 Class 7 Maths Question 5.Write the following decimal numbers in the expanded form:(i) 20.03(ii) 2.03(iii) 200.03(iv) 2.034Solution:(i) 20.03 2 10 0 1 0 1 3 110(ii) 2.03 2 1 0 1 3 110100100(iii) 200.03 2 100 0 10 0 1 0 1 3 1(iv) 2.034 2 1 0 1 3 1 4 10101011000100Ex 2.5 Class 7 Maths Question 6.Write the place value of 2 in the following decimal numbers:(i) 2.56(ii) 21.37(iii) 10.25(iv) 9.42(v) 63.352Solution:(i) Place value of 2 in 2.56 2 1 2 i.e. ones(ii) Place value of 2 in 21.37 2 10 20 i.e. tens(iii) Place value of 2 in 10.25 2 0.2 i.e. tenths10(iv) Place value of 2 in 9.42 2 0.02 i.e. hundredths100(v) Place value of 2 in 63.352 2 0.002 i.e. thousandths.1000Ex 2.5 Class 7 Maths Question 7.Dinesh went from place A to place B and from there to place C. A is 7.5 km from B and B is 12.7 km from C. Ayub went from place Ato place D and from there to place C. D is 9.3 km from A and C is 11.8 km from D. Who travelled more and by how much?Solution:Distance travelled by Dinesh from A to C AB BC 7.5 km - 12.7 km 20.2 kmDistance travelled by Ayub from A to C AD DC 9.3 km 11.8 km 21.1 kmSince 21.1 km 20.2 km.Hence, Ayub travelled more distance.Ex 2.5 Class 7 Maths Question 8.Shyama bought 5 kg 300 g apples and 3 kg 250 g mangoes. Sarala bought 4 kg 800 g oranges and 4 kg 150 g bananas. Who bought morefruits?Solution:Fruits bought by Shyama

5 kg 300 g apples 3 kg 250 g mangoes 5.300 kg apples 3.250 kg mangoes 8.550 kg of fruitsFruits bought by Sarala 4 kg 800 g oranges - 4 kg 150 g bananas 4.800 kg oranges 4.150 kg bananas 8.950 kg of fruitsSince 8.950 kg 8.550 kgHence, Sarala bought more fruits.Ex 2.5 Class 7 Maths Question 9.How much less is 28 km than 42.6 km?Solution:Since 28 km 42.6 kmHence, 28 km is less than 42.6 km by 14.6 km.

NCERT Solutions for Class 7 Maths Chapter 2 Fractions and Decimals Exercise 2.6Ex 2.6 Class 7 Maths Question 1.Find:(i) 0.2 6(ii) 8 4.6(iii) 2.71 5(iv) 20.1 4(v) 0.05 7(vi) 211.02 4(vii) 2 0.86Solution:(i) 0.2 6 2 6 12 and we have 1 digit right to the decimal point in 0.2.Thus 0.2 6 1.2(ii) 8 4.6 8 46 368 and there is one digit right to the decimal point in 4.6.Thus 8 4.6 36.8(iii) 2.71 5 271 5 1355 and there are two digits right to the decimal point in 2.71.Thus 2.71 5 13.55(iv) 20.1 4 201 4 804 and there is one digit right to the decimal point in 20.1. 20.1 4 80.4(v) 0.05 7 5 7 35 and there are 2 digits right to the decimal point in 0.05.Thus 0.05 7 0.35(vi) 211.02 4 21102 4 84408 and there are 2 digits right to the decimal point in 211.02.Thus 211.02 4 844.08(vii) 2 0.86 2 86 172 and there are 2 digits right to the decimal point in 0.86.Thus 2 0.86 1.72Ex 2.6 Class 7 Maths Question 2.Find the area of rectangle whose length is 5.7 cm and breadth is 3 cm.Solution:Length 5.7 cmBreadth 3 cmArea of rectangle length breadth 5.7 3 17.1 cm 2Hence, the required area 17.1 cm2Ex 2.6 Class 7 Maths Question 3.Find:(i) 1.3 10(ii) 36.8 10(iii) 153.7 10(iv) 168.07 10(v) 31.1 100(vi) 156.1 100(vii) 3.62 100

(viii) 43.07 100(ix) 0.5 10(x) 0.08 10(xi) 0.9 100(xii) 0.03 1000Solution:Ex 2.6 Class 7 Maths Question 4.A two-wheeler covers a distance of 55.3 km in one litre of petrol. How much distance will it cover is 10 litres of petrol?Solution:Distance covered in 1 litre 55.3 kmDistance covered in 10 litres 55.3 10 kmHence, the required distance 553 kmEx 2.6 Class 7 Maths Question 5.Find:(i) 2.5 0.3(ii) 0.1 51.7(iii) 0.2 316.8(iv) 1.3 3.1(v) 0.5 0.05(vi) 11.2 0.15(vii) 1.07 0.02(viii) 10.05 1.05(ix) 100.01 1.1(x) 100.01 1.1Solution:(i) 0 2.5 0.3 25 3 75 and there are 2 digits (1 1) right to the decimal points in 2.5 and 0.3.Thus 2.5 0.3 0.75(ii) 0.1 51.7 1 517 517 and there are two digits (1 1) right to the decimal places in 0.1 and 51.7.

(iii) 0.2 316.8 2 3168 6336 and there are 2 digits (1 1) right to the decimal points in 0.2 and 316.8.Thus 0.2 316.8 63.36.(iv) 1.3 3.1 13 31 403 and there are 2 digits (1 1) right to the decimal points in 1.3 and 3.1.Thus 1.3 3.1 – 4.03(v) 0.5 0.05 5 5 25 and there are 3 digits (1 2) right to the decimal points in 0.5 and 0.05.Thus 0.5 0.05 0.025(vi) 11.2 0.15 112 15 1680 and there are 3 digits (1 2) right to the decimal points in 11.2 and 0.15.Thus 11.2 0.15 1.680(vii) 1.07 0.02 107 2 214 and there are 4-digits (2 2) right to the decimal places is 1.07 0.02.Thus 1.07 0.02 0.0214(viii) 10.05 1.05 1005 105 105525 and there are 4 digits (2 2) right to the decimal places in 10.05 1.05.Thus 10.05 1.05 10.5525(ix) 101.01 0.01 10101 1 10101 and there are 4 digits (2 2) right to the decimal places in 101.01 and 0.01.Thus 101.01 0.01 1.0101(x) 100.01 1.1 10001 11 110011 and there are 3 digits (2 1) right to the decimal points in 100.01 and 1.1.Thus 100.01 1.1 110.011.

NCERT Solutions for Class 7 Maths Chapter 2 Fractions and Decimals Exercise 2.7Ex 2.7 Class 7 Maths Question 1.Find:(i) 0.4 2(ii) 0.35 5(iii) 2.48 4(iv) 65.4 6(v) 651.2 4(vi) 14.49 7(vii) 3.96 4(viii) 0.80 5Solution:

Ex 2.7 Class 7 Maths Question 2.Find:(i) 4.8 10(ii) 52.5 10(iii) 0.7 10(iv) 33.1 10(v) 272.23 10(vi) 0.56 10(vii) 3.97 10Solution:(i) 4.8 10 0.48 (Shifting the decimal point to the left by 1 place)(ii) 52.5 10 5.25 (Shifting the decimal point to the left by 1 place)(iii) 0.7 10 0.07 (Shifting the decimal point to the left by 1 place)(iv) 33.1 10 3.31 (Shifting the decimal point to the left by 1 place)(v) 272.23 10 27.223 (Shifting the decimal point to the left by 1 place)(vi) 0.56 4- 10 0.056(Shifting the decimal point to the left by 1 place)(vii) 3.97 10 0.397(Shifting the decimal point to the left by 1 place)Ex 2.7 Class 7 Maths Question 4.Find:(i) 7.9 1000(ii) 26.3 1000(iii) 38.53 1000(iv) 128.9 1000(v) 0.5 1000

Solution:(i) 7.9 1000 0.0079 (Shifting the decimal point to the left by 3 places)(ii) 26.3 1000 0.0263 (Shifting the decimal point to the left by 3 places)(iii) 38.53 1000 0.03853 (Shifting the decimal point to the left by 3 places)(iv) 128.9 1000 0.1289 (Shifting the decimal point to the left by 3 places)(v) 0.5 1000 0.0005 (Shifting the decimal point to the left by 3 places)Ex 2.7 Class 7 Maths Question 5.Find:(i) 7 3.5(ii) 36 0 .2(iii) 3.25 0.5(iv) 30.94 0.7(v) 0.5 0.25(vi) 7.75 0.25(vii) 76.5 0.15(viii) 37.8 1.4(ix) 2.73 1.3Solution:Ex 2.7 Class 7 Maths Question 6.A vehicle covers a distance of 43.2 km in 2.4 litres of Petrol. How much distance will it cover in one litre of petrol?Solution:2.4 litres of petrol is required to cover 43.2 km distance 1 litre of petrol will be required to cover 43.2Hence, the required distance 18 km

Ex 2.6 Class 7 Maths Question 4. A two-wheeler covers a distance of 55.3 km in one litre of petrol. How much distance will it cover is 10 litres of petrol? Solution: Distance covered in 1 litre 55.3 km Distance covered in 10 litres 55.3 10 km Hence, the required distance 553 km Ex 2.6 Class 7

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