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K KUNDAN 1. Two candidates contested the election. At the election 10% votes were rejected as invalid. The margin of the successful candidate was 308 and it was found that he had been sup- ported by 47% of the whole number on the voters’ list. What is the number of valid votes recorded by each candidate? 2. At a party 40% of the people have only orange juice and snacks, 10% have only food and 80% have snacks. If no- body has all three and everybody has something, how many have at least food? 3. In a certain community consisting of ‘p’ persons, x% can read and write. Among the males alone y% and of the fe- males alone m% can read and write. Find the number of males and females in the community. 4. A man spends 80% of his income. With the increase in the cost of living his expenses also increase by % 2 1 37 and his income increases by % 3 2 16 . Find his present percentage saving. 5. If the price of sugar falls by % 2 1 2 a person can buy 9 kg more of sugar for Rs 126 than before. If the price had risen by % 2 1 12 , how much sugar could he have bought for the same sum? 6. In an examination paper of 5 questions, 5% of the candi- dates answered all of them and 5% none. Of the rest, 25% answered only 1 question and 20% answered only 4. If % 2 1 24 of the entire candidates answered only 2 questions and 200 answered only 3, how many candidates appeared at the examination? 7. A sum of Rs 2368 was divided among 8 men, 10 women and 12 children in such a way that each man got 25% more than a woman and each woman got 25% more than a child. How much did each woman get? 8. In a school 20% of the students are below 5 years of age and the number of girls above 5 is 2 3 of the number of boys above 5 and equal to 64. How many students are there in the school? 9. 66 2 3 % of the employees of a company are skilled workers and the rest are unskilled. If 40% of the skilled workers and Percentage 30% of the unskilled workers are temporary, find the total number of employees when the toal number of permanent employees is 456. 10. Entry fee in an exhibition was Re 1. Later this was reduced by 25%, which increased the sale by 20%. Find the percent- age increase in the number of visitors. 11. Total population of a country is 98 × 10 7 , out of which 48 × 10 7 are females and the rest are males. Out of every 1000 males 98 can read and write but only 7.5% of the total popu- lation can do so. Find what percentage of women in the whole women population of the country can read and write. 12. In an examination paper of 6 questions, 5% of the candi- dates answered all the questions. Of the rest 10% answered only five questions out of six. Of the rest 20% answered only four questions out of six. Of the rest 25% answered only three questions out of six. Of the rest 3 1 33 % answered only two questions out of six. Of the rest 50% answered only one question out of six. Of the rest 100% were unable to solve any question out of the given six questions. There were 171 such students. Then what was the total number of candidates who appeared in the examination? 13. In a certain community consisting of ‘P’ persons, ‘a’ per cent can read and write. Of the males ‘b’ percent and of the fe- males ‘c’ percent can read and write. Find the number of males and females in the community. 14. In an examination paper of 6 questions, 4% of the candi- dates answered all of them and 6% none. Of the rest 20% answered only 1 question and 25% answered only 4. 15% of the entire candidates answered only 2 questions and 12½% only 3 questions. If 220 candidates answered only 5, how many candidates appeared at the examination? 15. The salaries of A, B and C together amount to Rs 25500. If they spend 85%, 80% and % 3 2 78 of their respective sala- ries, their savings are in the ratio 3 : 5 : 4. Find their respec- tive salaries. 16. There are two candidates in an election. 11% of the voters did not vote. 500 votes were declared invalid. The elected candidate got 3300 votes more than his opponent. If the elected candidate got 48% of the total votes, how many votes did each candidate get? 17. A man spends 75% of his income. With an increase in the cost of living his expenditure increases by % 3 1 33 and his income by 25%. Find his percentage of present saving.

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  • KKUNDAN

    1. Two candidates contested the election. At the election 10%votes were rejected as invalid. The margin of the successfulcandidate was 308 and it was found that he had been sup-ported by 47% of the whole number on the voters list. Whatis the number of valid votes recorded by each candidate?

    2. At a party 40% of the people have only orange juice andsnacks, 10% have only food and 80% have snacks. If no-body has all three and everybody has something, how manyhave at least food?

    3. In a certain community consisting of p persons, x% canread and write. Among the males alone y% and of the fe-males alone m% can read and write. Find the number of malesand females in the community.

    4. A man spends 80% of his income. With the increase in the

    cost of living his expenses also increase by %2137 and his

    income increases by %3216 . Find his present percentage

    saving.

    5. If the price of sugar falls by %212 a person can buy 9 kg

    more of sugar for Rs 126 than before. If the price had risen by

    %2112 , how much sugar could he have bought for the same

    sum?6. In an examination paper of 5 questions, 5% of the candi-

    dates answered all of them and 5% none. Of the rest, 25%answered only 1 question and 20% answered only 4. If

    %2124 of the entire candidates answered only 2 questions

    and 200 answered only 3, how many candidates appeared atthe examination?

    7. A sum of Rs 2368 was divided among 8 men, 10 women and12 children in such a way that each man got 25% more thana woman and each woman got 25% more than a child. Howmuch did each woman get?

    8. In a school 20% of the students are below 5 years of age and

    the number of girls above 5 is 2

    3of the number of boys above

    5 and equal to 64. How many students are there in the school?

    9. 662

    3% of the employees of a company are skilled workers

    and the rest are unskilled. If 40% of the skilled workers and

    Percentage30% of the unskilled workers are temporary, find the totalnumber of employees when the toal number of permanentemployees is 456.

    10. Entry fee in an exhibition was Re 1. Later this was reducedby 25%, which increased the sale by 20%. Find the percent-age increase in the number of visitors.

    11. Total population of a country is 98 107, out of which 48 107 are females and the rest are males. Out of every 1000males 98 can read and write but only 7.5% of the total popu-lation can do so. Find what percentage of women in thewhole women population of the country can read and write.

    12. In an examination paper of 6 questions, 5% of the candi-dates answered all the questions. Of the rest 10% answeredonly five questions out of six. Of the rest 20% answeredonly four questions out of six. Of the rest 25% answeredonly three questions out of six. Of the rest 3133 % answeredonly two questions out of six. Of the rest 50% answeredonly one question out of six. Of the rest 100% were unable tosolve any question out of the given six questions. Therewere 171 such students. Then what was the total number ofcandidates who appeared in the examination?

    13. In a certain community consisting of P persons, a per centcan read and write. Of the males b percent and of the fe-males c percent can read and write. Find the number ofmales and females in the community.

    14. In an examination paper of 6 questions, 4% of the candi-dates answered all of them and 6% none. Of the rest 20%answered only 1 question and 25% answered only 4. 15% ofthe entire candidates answered only 2 questions and 12%only 3 questions. If 220 candidates answered only 5, howmany candidates appeared at the examination?

    15. The salaries of A, B and C together amount to Rs 25500. If

    they spend 85%, 80% and %3278 of their respective sala-

    ries, their savings are in the ratio 3 : 5 : 4. Find their respec-tive salaries.

    16. There are two candidates in an election. 11% of the votersdid not vote. 500 votes were declared invalid. The electedcandidate got 3300 votes more than his opponent. If theelected candidate got 48% of the total votes, how manyvotes did each candidate get?

    17. A man spends 75% of his income. With an increase in the

    cost of living his expenditure increases by %3133 and his

    income by 25%. Find his percentage of present saving.

  • KKUNDAN

    1. Let x be the total voters.

    No. of votes cast = 109x

    Winner votes + Loser votes + 60 = 109x

    Loser votes

    = 100600043

    1004760

    109

    xxx

    According to the question,Winner Loser = 308

    or, 308100600043

    10047

    xx

    or, 3080060004347 xxor, 6200248004 xx Winner candidates valid votes

    = 47% of 6200 = 2914 Loser candidates valid votes

    2606100

    6000620043

    2.Juice Snacks (80)

    40

    0x y

    10

    FoodMaximum value of y = 80 40 = 40%Then maximum value of x = 100 (10 + 80) = 10% Maximum = 40 + 10 + 10 = 60% have food.

    3. Let the number of males and females in the community be Aand B respectively.A + B = p ....(i)From the question,y% of A + m% of B = x% of por, xpmByA ....(ii)Multiply by y in equation (i), we get

    ypyByA ....(iii)(ii) (iii)

    yxpyByAmByA or, yxpymB

    ymyxpB

    Putting the value of B in equation (i), we get

    ymyxppBpA

    =

    ymxmp

    4. Let the income of man be Rs x.

    Expenditure of man = 80% of x = Rs x54

    saving =

    54xx Rs 5

    x

    Answers and explanation

    New income = 630050 xxxx = Rs x6

    7

    New expenditure = 20075

    54

    54

    xx

    = xxxxx

    1011

    1038

    103

    54

    New saving = xx 1011

    67

    = Rs 15x

    % saving = %755100

    76

    15

    xx

    5. %212 of 126200

    5126 = Rs 2063

    Reduced price of 9 kg of sugar = Rs 2063

    Reduced price of 1 kg of sugar = 91

    2063

    = Re 207

    Let the original price of sugar be Rs 100.

    Reduced price = 212100 = Rs

    2195

    If reduced price is Rs 2

    195, then original price

    = Rs 100

    If reduced price is Re 207

    , then original price

    = Re 2019572100

    = Re 3914

    Now, increased in the price = 2112100

    = Rs 2

    225

    If original price is Rs 100, then increased price

    = Rs 2

    225

    If original price is Re 3914

    , then increased price

    = 3914

    1001

    2225

    = Re 5221

    Sugar bought for Rs 126 = 2152126 = 312 kg

    6. Let the total no. of candidates = xCandidate who answered 5 questions

    = 5% of 20xx

    Candidates who did not answer any question

  • KKUNDAN

    = 5% of 20xx

    Remaining candidates =

    2020xxx

    = xxx

    109

    10

    Candidates who answered 1 question

    = 25% of xx

    409

    109

    Candidates who answered 4 questions

    = 20% of xx

    509

    109

    Candidates who answered 2 questions only

    = %2124 of xx 200

    49

    Number of candidates who answered 3 questions

    =

    xxxxxx

    20049

    509

    409

    2020

    = 4200150 xxx

    Total no. of candidates = (x) = 4 200 = 8007. Suppose a child gets Rs x.

    A woman gets = Rs

    10025xx = Rs x

    45

    A man gets = Rs

    xx

    45 of %25

    45

    = Rs xxx 1625Rs

    165

    45

    8 men get = Rs 81625

    x = Rs x225

    10 women get = Rs 1045 = Rs x

    225

    12 children get = Rs x 12 = Rs 12x

    236812225

    225

    xxx

    or, 37x = 2368 372368

    x = Rs 64

    Each woman gets = 6445 = Rs 80

    8. Let the no, of students in the school = x no. of students below 5 years

    = 20% of x = x/5No. of girls who are above 5 years = 64 no. of boys who are above 5 years

    = 64 3/2 = 96

    No. of students above 5 years = x - x5

    45

    x ..... (i)

    No. of students in the school who are above5 years = 64 + 96 = 160 .... (ii)

    From (i) and (ii),45

    x = 160

    x = 160 5

    4

    = 2009. Let the total no. of the employees in the company be x.

    No. of skilled workers = 662

    3% of x =

    2

    3x

    unskilled workers = x - 2

    3 3

    x x

    temporary workers = 40% of 2

    3x + 30% of

    x

    3

    = 4

    15 10

    8 3x

    30

    11

    30x

    x x

    x

    permanent workers = x - 11

    30

    19

    30x x

    From the question,19

    30x = 456

    x = 456 30

    19

    = 720

    10. Let 100 persons visit the exhibition daily.Reduction in entry fee = 25% of Re 1 = Re 1/4

    Reduced entry fee = 1 - 1

    4 = Re

    3

    4Increase in sale of tickets due to reduction in entry fee = 20% total sale = 100 + 20% of 100 = Rs 120

    If entry fee is Re 3

    4, then no. of visitors = 1

    If entry fee is Rs 120, then no. of visitors

    =1 4 120

    3

    = 160

    increase in daily no. of visitors= 160 100 = 60%

    11. Total population = 980000000Number of males = 500000000Number of females = 480000000Number of persons who can read and write

    = 735000001005.7980000000

    No. of literate males

    = 49000000100098500000000

    No. of literate females = 73500000 - 49000000= 24500000

    Percentage of literate females

    = 48245

    48000000010024500000 = 5.104%

    12. Number of those students who answered zero question =171Suppose total number of students is T.

    Then,

    10025100

    10020100

    10010100

    1005100T

    100

    50100100

    3100100

    = 171

  • KKUNDAN

    or, 17110050

    300200

    10075

    10080

    10090

    10095T

    or, 100050200758090950003000000000171T

    13. Let the number of males and females be M and F respec-tivelyThen M + F = PSince, of the males b per cent can read and write, then num-

    ber of literate males = M100b

    Similarly, number of literate females = F100c

    But total number of literate people = P100a

    P100aF100

    cM100b

    bM + cF = aPor, bM + c(P - M) = aPor, bM + cP - cM = aPor, M(b - c) = P(a - c)

    or, cb

    caPM

    males

    Also bM + cF = aPor, b(P - F) + cF = aPor, bP - bF + cF = aPor, F(c - b) = P(a - b)

    or, F = bc

    baP

    females

    14. Suppose total number of candidates = 100Candidates who answered 6 questions

    = 4% of 100 = 4Candidates who didnt answer any question

    = 6% of 100 = 6Remaining candidates = 100 - 10 = 90No. of candidates who answered only 1 question = 20% of90 = 18No. of candidates who answered only 4 questions = 25% of

    90 = 2122

    Candidates who answered only 2 questions= 15% of 100 = 15

    Candidates who answered only 3 questions

    = 2112 % of 100 = 2

    112

    No. of candidates who answered 5 questions

    = 22211215

    21221864100

    If 5 questions are answered by 22 candidates then total no.of candidates =100

    total no. of candidates = 100022022100

    15. Let the salaries of A, B and C be Rs x, Rs y and Rs z respec-tively.Expenditure of A = 85% of x

    Savings of A = 15% of x = Rs 20x3

    Expenditure of B = 80% of ySavings of B = 20% of y = Rs y/5

    Expenditure of C = %3278 of z

    Savings of C = %3121 of z = Rs 75

    z16

    From the question,

    75z16:5

    y:20x3 = 3 : 5 : 4

    x : y : z = 16475:55:3

    203

    = 20 : 25 : 475 = 80 : 100 : 75 = 16 : 20 : 15

    Salary of A = 255005116 = Rs 8000

    Salary of B = 255005120 = Rs 10000

    Salary of C = 255005115 = Rs 7500

    16. Let the total no. of votes = x% of voters who did not vote = 11%

    no. of votes polled = 100x89

    10011xx

    Number of invalid votes = 500 no. of valid votes = (0.89x - 500) .... (i)Elected candidate gets 0.48x votes. Therefore0.48x + (0.48x 3300) = 0.89x 500or, 0.07x + 500 = 3300or, 0.07x = 2800or, x = 2800/0.07 = 40000 no. of votes secured by elected candidate

    = 0.48x = 19200.No. of votes secured by loser candidate

    = 19200 3300 = 1590017. Let his income be Rs 100.

    expenses = 75% of 100 = Rs 75. savings = 100 75 = Rs 25.

    Increased expenditure = 75 + 75 300100

    = 75 + 25 = Rs 100.

    Increased income = 125Rs10025100100

    New savings = 125 100 = Rs 25.

    % savings = %2010012525