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Chapter 4

Fractions — Exercise 4(E)

Class - 6 RS Aggarwal Mathematics Solutions



Exercise 4(E)

Question 1

Find the product :

57×23\dfrac{5}{7} \times \dfrac{2}{3}

Answer

57×235×27×31021\Rightarrow \dfrac{5}{7} \times \dfrac{2}{3}\\[1em] \Rightarrow \dfrac{5 \times 2}{7 \times 3}\\[1em] \Rightarrow \dfrac{10}{21}

Hence, 57×23=1021\dfrac{5}{7} \times \dfrac{2}{3} = \dfrac{10}{21}.

Question 2

Find the product :

35×49\dfrac{3}{5} \times \dfrac{4}{9}

Answer

35×493×45×91245415\Rightarrow \dfrac{3}{5} \times \dfrac{4}{9}\\[1em] \Rightarrow \dfrac{3 \times 4}{5 \times 9}\\[1em] \Rightarrow \dfrac{12}{45}\\[1em] \Rightarrow \dfrac{4}{15}

Hence, 35×49=415\dfrac{3}{5} \times \dfrac{4}{9} = \dfrac{4}{15}.

Question 3

Find the product :

1235×1427\dfrac{12}{35} \times \dfrac{14}{27}

Answer

1235×14271227×143549×25845.\Rightarrow \dfrac{12}{35} \times \dfrac{14}{27}\\[1em] \Rightarrow \dfrac{12}{27} \times \dfrac{14}{35} \\[1em] \Rightarrow \dfrac{4}{9} \times \dfrac{2}{5} \\[1em] \Rightarrow \dfrac{8}{45}.

Hence, 1235×1427=845\dfrac{12}{35} \times \dfrac{14}{27} = \dfrac{8}{45}.

Question 4

Find the product :

3051×1725\dfrac{30}{51} \times \dfrac{17}{25}

Answer

3051×17253025×175165×1325.\Rightarrow \dfrac{30}{51} \times \dfrac{17}{25}\\[1em] \Rightarrow \dfrac{30}{25} \times \dfrac{17}{51} \\[1em] \Rightarrow \dfrac{6}{5} \times \dfrac{1}{3} \\[1em] \Rightarrow \dfrac{2}{5}.

Hence, 3051×1725=25\dfrac{30}{51} \times \dfrac{17}{25} = \dfrac{2}{5}.

Question 5

Find the product :

916×1415\dfrac{9}{16} \times \dfrac{14}{15}

Answer

916×1415915×141635×782140.\Rightarrow \dfrac{9}{16} \times \dfrac{14}{15}\\[1em] \Rightarrow \dfrac{9}{15} \times \dfrac{14}{16} \\[1em] \Rightarrow \dfrac{3}{5} \times \dfrac{7}{8} \\[1em] \Rightarrow \dfrac{21}{40}.

Hence, 916×1415=2140\dfrac{9}{16} \times \dfrac{14}{15} = \dfrac{21}{40}.

Question 6

Find the product :

21127×182\dfrac{11}{27} \times 18

Answer

21127×186527×1865×182765×2313034313.\Rightarrow 2\dfrac{11}{27} \times 18\\[1em] \Rightarrow \dfrac{65}{27} \times 18\\[1em] \Rightarrow 65 \times \dfrac{18}{27} \\[1em] \Rightarrow 65 \times \dfrac{2}{3} \\[1em] \Rightarrow \dfrac{130}{3} \\[1em] \Rightarrow 43\dfrac{1}{3}.

Hence, 21127×18=43132\dfrac{11}{27} \times 18 = 43\dfrac{1}{3}.

Question 7

Find the product :

7112×8177\dfrac{1}{12} \times \dfrac{8}{17}

Answer

7112×8178512×8178517×8125×23103313.\Rightarrow 7\dfrac{1}{12} \times \dfrac{8}{17}\\[1em] \Rightarrow \dfrac{85}{12} \times \dfrac{8}{17}\\[1em] \Rightarrow \dfrac{85}{17} \times \dfrac{8}{12} \\[1em] \Rightarrow 5 \times \dfrac{2}{3} \\[1em] \Rightarrow \dfrac{10}{3}\\[1em] \Rightarrow 3\dfrac{1}{3}.

Hence, 7112×817=3137\dfrac{1}{12} \times \dfrac{8}{17} = 3\dfrac{1}{3}.

Question 8

Find the product :

8121×11138\dfrac{1}{21} \times 1\dfrac{1}{13}

Answer

8121×111316921×141316913×142113×23263823.\Rightarrow 8\dfrac{1}{21} \times 1\dfrac{1}{13}\\[1em] \Rightarrow \dfrac{169}{21} \times \dfrac{14}{13}\\[1em] \Rightarrow \dfrac{169}{13} \times \dfrac{14}{21} \\[1em] \Rightarrow 13 \times \dfrac{2}{3} \\[1em] \Rightarrow \dfrac{26}{3} \\[1em] \Rightarrow 8\dfrac{2}{3}.

Hence, 8121×1113=8238\dfrac{1}{21} \times 1\dfrac{1}{13} = 8\dfrac{2}{3}.

Question 9

Find the product :

7711×63167\dfrac{7}{11} \times 6\dfrac{3}{16}

Answer

7711×63168411×99168416×9911214×918944714.\Rightarrow 7\dfrac{7}{11} \times 6\dfrac{3}{16}\\[1em] \Rightarrow \dfrac{84}{11} \times \dfrac{99}{16}\\[1em] \Rightarrow \dfrac{84}{16} \times \dfrac{99}{11} \\[1em] \Rightarrow \dfrac{21}{4} \times 9 \\[1em] \Rightarrow \dfrac{189}{4} \\[1em] \Rightarrow 47\dfrac{1}{4}.

Hence, 7711×6316=47147\dfrac{7}{11} \times 6\dfrac{3}{16} = 47\dfrac{1}{4}.

Question 10

Find the product :

1114×67911\dfrac{1}{4} \times 6\dfrac{7}{9}

Answer

1114×679454×619459×6145×61430547614.\Rightarrow 11\dfrac{1}{4} \times 6\dfrac{7}{9}\\[1em] \Rightarrow \dfrac{45}{4} \times \dfrac{61}{9}\\[1em] \Rightarrow \dfrac{45}{9} \times \dfrac{61}{4} \\[1em] \Rightarrow 5 \times \dfrac{61}{4} \\[1em] \Rightarrow \dfrac{305}{4} \\[1em] \Rightarrow 76\dfrac{1}{4}.

Hence, 1114×679=761411\dfrac{1}{4} \times 6\dfrac{7}{9} = 76\dfrac{1}{4}.

Question 11

Find the product :

134×217×4451\dfrac{3}{4} \times 2\dfrac{1}{7} \times 4\dfrac{4}{5}

Answer

134×217×44574×157×24577×155×2441×3×618.\Rightarrow 1\dfrac{3}{4} \times 2\dfrac{1}{7} \times 4\dfrac{4}{5}\\[1em] \Rightarrow \dfrac{7}{4} \times \dfrac{15}{7} \times \dfrac{24}{5}\\[1em] \Rightarrow \dfrac{7}{7} \times \dfrac{15}{5} \times \dfrac{24}{4} \\[1em] \Rightarrow 1 \times 3\times 6 \\[1em] \Rightarrow 18.

Hence, 134×217×445=181\dfrac{3}{4} \times 2\dfrac{1}{7} \times 4\dfrac{4}{5} = 18.

Question 12

Find the product :

316×234×24113\dfrac{1}{6} \times 2\dfrac{3}{4} \times 2\dfrac{4}{11}

Answer

316×234×2411196×114×2611196×1111×264196×1×1322471220712.\Rightarrow 3\dfrac{1}{6} \times 2\dfrac{3}{4} \times 2\dfrac{4}{11}\\[1em] \Rightarrow \dfrac{19}{6} \times \dfrac{11}{4} \times \dfrac{26}{11}\\[1em] \Rightarrow \dfrac{19}{6} \times \dfrac{11}{11} \times \dfrac{26}{4} \\[1em] \Rightarrow \dfrac{19}{6} \times 1 \times \dfrac{13}{2} \\[1em] \Rightarrow \dfrac{247}{12} \\[1em] \Rightarrow 20\dfrac{7}{12}.

Hence, 316×234×2411=207123\dfrac{1}{6} \times 2\dfrac{3}{4} \times 2\dfrac{4}{11} = 20\dfrac{7}{12}.

Question 13

Find the reciprocal of :

(i) 59\dfrac{5}{9}

(ii) 713\dfrac{7}{13}

(iii) 8

(iv) 15\dfrac{1}{5}

(v) 3253\dfrac{2}{5}

(vi) 8198\dfrac{1}{9}

(vii) 5385\dfrac{3}{8}

(viii) 23

Answer

The reciprocal of a non-zero fraction is a fraction obtained by swapping its numerator and denominator, so that their product is 1.

(i) 59\dfrac{5}{9}

Hence, the reciprocal of 59=95\dfrac{5}{9} = \dfrac{9}{5}.

(ii) 713\dfrac{7}{13}

Hence, the reciprocal of 713=137\dfrac{7}{13} = \dfrac{13}{7}.

(iii) 88

Hence, the reciprocal of 8=188 = \dfrac{1}{8}.

(iv) 15\dfrac{1}{5}

Hence, the reciprocal of 15=51=5\dfrac{1}{5} = \dfrac{5}{1} = 5.

(v) 3253\dfrac{2}{5}

175\Rightarrow \dfrac{17}{5}

Hence, the reciprocal of 175=517\dfrac{17}{5} = \dfrac{5}{17}.

(vi) 8198\dfrac{1}{9}

739\Rightarrow \dfrac{73}{9}

Hence, the reciprocal of 739=973\dfrac{73}{9} = \dfrac{9}{73}.

(vii) 5385\dfrac{3}{8}

438\Rightarrow \dfrac{43}{8}

Hence, the reciprocal of 438=843\dfrac{43}{8} = \dfrac{8}{43}.

(viii) 23

Hence, the reciprocal of 23=231=12323 = \dfrac{23}{1} = \dfrac{1}{23}.

Question 14

Divide:

1321÷27\dfrac{13}{21} ÷ \dfrac{2}{7}

Answer

1321÷271321×72132×721132×13136216.\Rightarrow \dfrac{13}{21} ÷ \dfrac{2}{7}\\[1em] \Rightarrow \dfrac{13}{21} \times \dfrac{7}{2}\\[1em] \Rightarrow \dfrac{13}{2} \times \dfrac{7}{21} \\[1em] \Rightarrow \dfrac{13}{2} \times \dfrac{1}{3} \\[1em] \Rightarrow \dfrac{13}{6} \\[1em] \Rightarrow 2\dfrac{1}{6}.

Hence, 1321÷27=216\dfrac{13}{21} ÷ \dfrac{2}{7} = 2\dfrac{1}{6}.

Question 15

Divide:

318÷53\dfrac{1}{8} ÷ 5

Answer

318÷5258×1525×18×5254058.\Rightarrow 3\dfrac{1}{8} ÷ 5\\[1em] \Rightarrow \dfrac{25}{8} \times \dfrac{1}{5}\\[1em] \Rightarrow \dfrac{25 \times 1}{8 \times 5}\\[1em] \Rightarrow \dfrac{25}{40}\\[1em] \Rightarrow \dfrac{5}{8}.

Hence, 318÷5=583\dfrac{1}{8} ÷ 5 = \dfrac{5}{8}.

Question 16

Divide:

1÷2351 ÷ 2\dfrac{3}{5}

Answer

1÷2351÷1351×513513.\Rightarrow 1 ÷ 2\dfrac{3}{5}\\[1em] \Rightarrow 1 ÷ \dfrac{13}{5}\\[1em] \Rightarrow 1 \times \dfrac{5}{13}\\[1em] \Rightarrow \dfrac{5}{13}.

Hence, 1÷235=5131 ÷ 2\dfrac{3}{5} = \dfrac{5}{13}.

Question 17

Divide:

759÷347\dfrac{5}{9} ÷ 34

Answer

759÷34689÷34689×1346834×192×1929.\Rightarrow 7\dfrac{5}{9} ÷ 34\\[1em] \Rightarrow \dfrac{68}{9} ÷ 34\\[1em] \Rightarrow \dfrac{68}{9} \times \dfrac{1}{34}\\[1em] \Rightarrow \dfrac{68}{34} \times \dfrac{1}{9} \\[1em] \Rightarrow 2 \times \dfrac{1}{9} \\[1em] \Rightarrow \dfrac{2}{9}.

Hence, 759÷34=297\dfrac{5}{9} ÷ 34 = \dfrac{2}{9}.

Question 18

Divide:

70÷82570 ÷ 8\dfrac{2}{5}

Answer

Solving,

70÷825701÷425701×5427042×553×5253813.\Rightarrow 70 ÷ 8\dfrac{2}{5}\\[1em] \Rightarrow \dfrac{70}{1} ÷ \dfrac{42}{5}\\[1em] \Rightarrow \dfrac{70}{1} \times \dfrac{5}{42}\\[1em] \Rightarrow \dfrac{70}{42} \times 5 \\[1em] \Rightarrow \dfrac{5}{3} \times 5 \\[1em] \Rightarrow \dfrac{25}{3}\\[1em] \Rightarrow 8\dfrac{1}{3}.

Hence, 70÷825=81370 ÷ 8\dfrac{2}{5} = 8\dfrac{1}{3}.

Question 19

Divide:

412÷6124\dfrac{1}{2} ÷ 6\dfrac{1}{2}

Answer

Solving,

412÷61292÷13292×2139×22×13913.\Rightarrow 4\dfrac{1}{2} ÷ 6\dfrac{1}{2}\\[1em] \Rightarrow \dfrac{9}{2} ÷ \dfrac{13}{2}\\[1em] \Rightarrow \dfrac{9}{2} \times \dfrac{2}{13}\\[1em] \Rightarrow \dfrac{9 \times 2}{2 \times 13}\\[1em] \Rightarrow \dfrac{9}{13}.

Hence, 412÷612=9134\dfrac{1}{2} ÷ 6\dfrac{1}{2} = \dfrac{9}{13}.

Question 20

Divide:

5710÷3165\dfrac{7}{10} ÷ 3\dfrac{1}{6}

Answer

Solving,

5710÷3165710÷1965710×6195719×6103×3595145.\Rightarrow 5\dfrac{7}{10} ÷ 3\dfrac{1}{6}\\[1em] \Rightarrow \dfrac{57}{10} ÷ \dfrac{19}{6}\\[1em] \Rightarrow \dfrac{57}{10} \times \dfrac{6}{19}\\[1em] \Rightarrow \dfrac{57}{19} \times \dfrac{6}{10} \\[1em] \Rightarrow 3 \times \dfrac{3}{5}\\[1em] \Rightarrow \dfrac{9}{5}\\[1em] \Rightarrow 1\dfrac{4}{5}.

Hence, 5710÷316=1455\dfrac{7}{10} ÷ 3\dfrac{1}{6} = 1\dfrac{4}{5}.

Question 21

Divide:

1057÷1111410\dfrac{5}{7} ÷ 1\dfrac{11}{14}

Answer

Solving,

1057÷11114757÷2514757×14257525×1473×26.\Rightarrow 10\dfrac{5}{7} ÷ 1\dfrac{11}{14}\\[1em] \Rightarrow \dfrac{75}{7} ÷ \dfrac{25}{14}\\[1em] \Rightarrow \dfrac{75}{7} \times \dfrac{14}{25}\\[1em] \Rightarrow \dfrac{75}{25} \times \dfrac{14}{7}\\[1em] \Rightarrow 3 \times 2 \\[1em] \Rightarrow 6.

Hence, 1057÷11114=610\dfrac{5}{7} ÷ 1\dfrac{11}{14} = 6.

Question 22

Divide:

1589÷32315\dfrac{8}{9} ÷ 3\dfrac{2}{3}

Answer

Solving,

1589÷3231439÷1131439×31114311×3913×13133413.\Rightarrow 15\dfrac{8}{9} ÷ 3\dfrac{2}{3}\\[1em] \Rightarrow \dfrac{143}{9} ÷ \dfrac{11}{3}\\[1em] \Rightarrow \dfrac{143}{9} \times \dfrac{3}{11}\\[1em] \Rightarrow \dfrac{143}{11} \times \dfrac{3}{9} \\[1em] \Rightarrow 13 \times \dfrac{1}{3} \\[1em] \Rightarrow \dfrac{13}{3} \\[1em] \Rightarrow 4\dfrac{1}{3}.

Hence, 1589÷323=41315\dfrac{8}{9} ÷ 3\dfrac{2}{3} = 4\dfrac{1}{3}

Question 23

Divide:

945÷323259\dfrac{4}{5} ÷ 3\dfrac{23}{25}

Answer

Solving,

945÷32325495÷9825495×25984998×25512×552212.\Rightarrow 9\dfrac{4}{5} ÷ 3\dfrac{23}{25}\\[1em] \Rightarrow \dfrac{49}{5} ÷ \dfrac{98}{25}\\[1em] \Rightarrow \dfrac{49}{5} \times \dfrac{25}{98}\\[1em] \Rightarrow \dfrac{49}{98} \times \dfrac{25}{5} \\[1em] \Rightarrow \dfrac{1}{2} \times 5 \\[1em] \Rightarrow \dfrac{5}{2} \\[1em] \Rightarrow 2\dfrac{1}{2}.

Hence, 945÷32325=2129\dfrac{4}{5} ÷ 3\dfrac{23}{25} = 2\dfrac{1}{2}.

Question 24

Divide:

21738÷112192\dfrac{17}{38} ÷ 1\dfrac{12}{19}

Answer

Solving,

21738÷112199338÷31199338×19319331×19383×1232112.\Rightarrow 2\dfrac{17}{38} ÷ 1\dfrac{12}{19}\\[1em] \Rightarrow \dfrac{93}{38} ÷ \dfrac{31}{19}\\[1em] \Rightarrow \dfrac{93}{38} \times \dfrac{19}{31}\\[1em] \Rightarrow \dfrac{93}{31} \times \dfrac{19}{38}\\[1em] \Rightarrow 3 \times \dfrac{1}{2}\\[1em] \Rightarrow \dfrac{3}{2}\\[1em] \Rightarrow 1\dfrac{1}{2}.

Hence, 21738÷11219=1122\dfrac{17}{38} ÷ 1\dfrac{12}{19} = 1\dfrac{1}{2}.

Question 25

Divide:

8725÷31158\dfrac{7}{25} ÷ 3\dfrac{1}{15}

Answer

Solving,

8725÷311520725÷461520725×154620746×152592×3527102710.\Rightarrow 8\dfrac{7}{25} ÷ 3\dfrac{1}{15}\\[1em] \Rightarrow \dfrac{207}{25} ÷ \dfrac{46}{15}\\[1em] \Rightarrow \dfrac{207}{25} \times \dfrac{15}{46}\\[1em] \Rightarrow \dfrac{207}{46} \times \dfrac{15}{25} \\[1em] \Rightarrow \dfrac{9}{2} \times \dfrac{3}{5} \\[1em] \Rightarrow \dfrac{27}{10}\\[1em] \Rightarrow 2\dfrac{7}{10}.

Hence, 8725÷3115=27108\dfrac{7}{25} ÷ 3\dfrac{1}{15} = 2\dfrac{7}{10}.

Question 26

The cost of 1 litre of milk is ₹ 423542\dfrac{3}{5}. Find the cost of 121212\dfrac{1}{2} litres of milk.

Answer

Given, the cost of 1 litre of milk = ₹ 423542\dfrac{3}{5}

The cost of 121212\dfrac{1}{2} litres of milk :

=4235×1212=2135×252=2132×255=2132×5=10652=53212.= ₹42\dfrac{3}{5} \times 12\dfrac{1}{2}\\[1em] = ₹\dfrac{213}{5} \times \dfrac{25}{2}\\[1em] = ₹\dfrac{213}{2} \times \dfrac{25}{5}\\[1em] = ₹\dfrac{213}{2} \times 5 \\[1em] = ₹\dfrac{1065}{2}\\[1em] = ₹ 532\dfrac{1}{2}.

Hence, the cost of 121212\dfrac{1}{2} litres of milk = ₹ 53212532\dfrac{1}{2}.

Question 27

The cost of 1 litre of petrol is ₹ 653465\dfrac{3}{4}. Find the cost of 36 litres of petrol.

Answer

Given, the cost of 1 litre of petrol = ₹ 653465\dfrac{3}{4}

The cost of 36 litres of petrol

=6534×36=2634×36=263×364=94684=2,367= ₹ 65\dfrac{3}{4} \times 36\\[1em] = ₹ \dfrac{263}{4} \times 36\\[1em] = ₹ \dfrac{263 \times 36}{4} \\[1em] = ₹ \dfrac{9468}{4} \\[1em] = ₹ 2,367

Hence, the cost of 36 litres of petrol = ₹ 2,367.

Question 28

The cost of 3123\dfrac{1}{2} metres of cloth is ₹ 54734547\dfrac{3}{4}. Find the cost of 1 metre of cloth.

Answer

Given, the cost of 3123\dfrac{1}{2} metres of cloth = ₹ 54734547\dfrac{3}{4}

The cost of 1 m of cloth :

=54734÷312=2,1914÷72=2,1914×27=2,1917×24=313×12=3132=15612.= 547\dfrac{3}{4} ÷ 3\dfrac{1}{2}\\[1em] = \dfrac{2,191}{4} ÷ \dfrac{7}{2}\\[1em] = \dfrac{2,191}{4} \times \dfrac{2}{7}\\[1em] = \dfrac{2,191}{7} \times \dfrac{2}{4}\\[1em] = 313 \times \dfrac{1}{2}\\[1em] = \dfrac{313}{2}\\[1em] = 156\dfrac{1}{2}.

Hence, the cost of 1 metre of cloth = ₹ 15612156\dfrac{1}{2}.

Question 29

Tanvy cuts 54 m of cloth into pieces, each of length 3383\dfrac{3}{8} m. How many pieces does she get?

Answer

Given, total length of cloth = 54 m

Length of each piece = 3383\dfrac{3}{8} m

Let n be the number of pieces.

By formula,

Total length = Number of pieces x length of each piece

n×338=54n×278=54n=54÷278n=54×827n=5427×8n=2×8n=16.\Rightarrow n \times 3\dfrac{3}{8} = 54\\[1em] \Rightarrow n \times \dfrac{27}{8} = 54\\[1em] \Rightarrow n = 54 ÷ \dfrac{27}{8}\\[1em] \Rightarrow n = 54 \times \dfrac{8}{27}\\[1em] \Rightarrow n = \dfrac{54}{27} \times 8 \\[1em] \Rightarrow n = 2 \times 8 \\[1em] \Rightarrow n = 16.

Hence, the number of pieces = 16.

Question 30

A cord of length 12612126\dfrac{1}{2} m has been cut into 46 pieces of equal length. What is the length of each piece?

Answer

Given, total length of cord = 12612126\dfrac{1}{2} m

Number of pieces = 46

Let x be the length of each piece.

By formula,

Total length = Number of pieces x length of each piece

46×x=1261246×x=2532x=2532÷46x=2532×146x=25346×12x=25392x=23×1123×4x=114x=234.\Rightarrow 46 \times x = 126\dfrac{1}{2}\\[1em] \Rightarrow 46 \times x = \dfrac{253}{2} \\[1em] \Rightarrow x = \dfrac{253}{2} ÷ 46\\[1em] \Rightarrow x = \dfrac{253}{2} \times \dfrac{1}{46} \\[1em] \Rightarrow x = \dfrac{253}{46} \times \dfrac{1}{2} \\[1em] \Rightarrow x = \dfrac{253}{92} \\[1em] \Rightarrow x = \dfrac{23 \times 11}{23 \times 4} \\[1em] \Rightarrow x = \dfrac{11}{4} \\[1em] \Rightarrow x = 2\dfrac{3}{4}.

Hence, the length of each piece = 2342\dfrac{3}{4} m.

Question 31

A car travels 28312283\dfrac{1}{2} km in 4234\dfrac{2}{3} hours. How far does it go in 1 hour?

Answer

Given, total distance = 28312283\dfrac{1}{2} km

Total time = 4234\dfrac{2}{3} hours

Let x be the distance covered in 1 hour.

By formula,

Distance covered in 1 hour x Total time = Total distance

x×423=28312x×143=5672x=5672÷143x=5672×314x=56714×32x=812×32x=2434x=6034.\Rightarrow x \times 4\dfrac{2}{3} = 283\dfrac{1}{2}\\[1em] \Rightarrow x \times \dfrac{14}{3} = \dfrac{567}{2}\\[1em] \Rightarrow x = \dfrac{567}{2} ÷ \dfrac{14}{3}\\[1em] \Rightarrow x = \dfrac{567}{2} \times \dfrac{3}{14}\\[1em] \Rightarrow x = \dfrac{567}{14} \times \dfrac{3}{2} \\[1em] \Rightarrow x = \dfrac{81}{2} \times \dfrac{3}{2} \\[1em] \Rightarrow x = \dfrac{243}{4} \\[1em] \Rightarrow x = 60\dfrac{3}{4}.

Hence, distance covered in 1 hour = 603460\dfrac{3}{4} km.

Question 32

The area of a rectangular plot of land is 462546\dfrac{2}{5} sq.m. If its length is 7147\dfrac{1}{4} m, find its breadth.

Answer

Given, the area of a rectangular plot of land = 462546\dfrac{2}{5} sq. m

Length of rectangular plot = 7147\dfrac{1}{4} m

Let b be the breath of the rectangular plot.

By formula, length x breadth = area

714×b=4625294×b=2325b=2325÷294b=2325×429b=232×45×29b=23229×45b=8×45b=325b=625.\Rightarrow 7\dfrac{1}{4} \times b = 46\dfrac{2}{5}\\[1em] \Rightarrow \dfrac{29}{4} \times b = \dfrac{232}{5}\\[1em] \Rightarrow b = \dfrac{232}{5} ÷ \dfrac{29}{4}\\[1em] \Rightarrow b = \dfrac{232}{5} \times \dfrac{4}{29}\\[1em] \Rightarrow b = \dfrac{232 \times 4}{5 \times 29}\\[1em] \Rightarrow b = \dfrac{232}{29} \times \dfrac{4}{5} \\[1em] \Rightarrow b = 8 \times \dfrac{4}{5} \\[1em] \Rightarrow b = \dfrac{32}{5}\\[1em] \Rightarrow b = 6\dfrac{2}{5}.

Hence, the breadth of the rectangular plot = 6256\dfrac{2}{5} m.

Question 33

The product of two fractions is 153415\dfrac{3}{4}. If one of them is 4124\dfrac{1}{2}, find the other.

Answer

Given, the product of two fractions = 153415\dfrac{3}{4}

One of the fraction = 4124\dfrac{1}{2}

Let x be the other fraction.

x×412=1534x=1534÷412=634÷92=634×29=63×24×9=12636=72=312.\Rightarrow x \times 4\dfrac{1}{2} = 15\dfrac{3}{4} \\[1em] \Rightarrow x = 15\dfrac{3}{4} ÷ 4\dfrac{1}{2}\\[1em] = \dfrac{63}{4} ÷ \dfrac{9}{2}\\[1em] = \dfrac{63}{4} \times \dfrac{2}{9}\\[1em] = \dfrac{63 \times 2}{4 \times 9}\\[1em] = \dfrac{126}{36}\\[1em] = \dfrac{7}{2}\\[1em] = 3\dfrac{1}{2}.

Hence, the other fraction = 3123\dfrac{1}{2}.

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