SSC CGLE 2015 doubts in Quantitative Aptitude

edited May 2015 in SSC
this thread has been made to share your doubts in maths portion and discuss its solutions/shortcuts
guys do contribute any doubt you encounter or soln to the doubts posted on this thread.senior players are requested to share their tricks

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  • 1) A and B can complete a job in 8 days.both b and C,working alone can finish the same job in 12 days. A and B commence work on the job and work for 4 days,then A leaves and B continues for 2 more days and then leaves too.C now starts working,and finishes the job .how many days did C require?
  • 2)IF (1+SINA) (1+SINB) (1+SINC) = (1-SINA) (1-SINB) (1-SINC),then find the value of each side of triangle
  • 3)if goods are purchased for rs 450 and one third sold at a loss of 10%.at what gain percent should the remainder be sold so as to gain 20% on the whole transaction?
  • 1) A and B can complete a job in 8 days.both b and C,working alone can finish the same job in 12 days. A and B commence work on the job and work for 4 days,then A leaves and B continues for 2 more days and then leaves too.C now starts working,and finishes the job .how many days did C require?
    4
    2014-1st attempt,mains--pol science
  • @hummingbird bhai plz give the trick/methodology/concept behind it,as i also know their answers(since they are from prev yrs qps,but i dont know the solution),thanx in advance
  • @hummingbird bhai plz give the trick/methodology/concept behind it,as i also know their answers(since they are from prev yrs qps,but i dont know the solution),thanx in advance
    no trick sol is simple
    a and b are able to finish work in 8 days so they will finish half work in 4 days.rest of 1/2 work which would done by b and c.b works for 2 additional days so b does 2/12=1/6 work in two days.remaking work left=1/2-1/6=1/3 which will done by c in 4 days as 12/3=4

    2014-1st attempt,mains--pol science
  • geo,trigo,&mensuration are very well explained in sarvesh verma,but dont go beyond level one,rest go with kiran prakashan paperset and topicwise questions at the end of papers
  • 4) what will be the minimum value of (x-2) (x-9) ?
  • 5)a fruit seller buys some oranges @ 4 for rs 10 and an equal number more @ 5 for rs 10.he sells the whole lot at 9 for rs 20.what is his loss or gain % ?
  • 6) a man ordered four pair of black socks.the price of a black sock is double that of a brown pair.while preparing the bill ,the clerk interchanged the no of black & brown sock socks by mistake which increased the bill by 50%.what will be the ratio of black and brown pair in original order?
  • @captainx @hummingbird
    Which is the best book for numerical aptitude?
  • bhai im fillowing sarvesh verma for last 4 months and i find it the best in termsof concrptual clarity/practice ques/trics.....the remaining thing can be coverde by kiran prakashans paperset
  • 1) A and B can complete a job in 8 days.both b and C,working alone can finish the same job in 12 days. A and B commence work on the job and work for 4 days,then A leaves and B continues for 2 more days and then leaves too.C now starts working,and finishes the job .how many days did C require?
    Let the total work be 24 units (LCM of 8 and 12)
    Therefore (A+B)'s work in 1 day will be = 24/8 = 3 units
    B and C alone complete work in 12 days.
    Therefore B and C both alone do 24/12 =2 units in 1 day.
    A's alone 1 day work= (A+B)-B = 3-2 =1
    Therefore A and B together complete in 4 days = 4 x 3 = 12 units
    remaining work= 24-12 = 12 units
    B alone works for next two days = 2x2 = 4 units of work
    remaining work = 12-4 = 8 units
    C completes 2units of work in 1 day
    therefore, he will complete 8 units of work in = 8/2 = 4days
    Therefore answer is 4days

    PS. We usually do it in short but for ur understanding i elaborated each step :)
  • 4) what will be the minimum value of (x-2) (x-9) ?
    The minimum value will be -6
    If you put x= 0, then then we will get 18. If you put x= 10, then you will get 8. However, if you put a number x between 2 and 9, it will generate negative answer. So one number less than 9 i.e. 8. If we put x=8, then we will get the value as (8-2)(8-9) = -6. This can be the least value formed
  • 5)a fruit seller buys some oranges @ 4 for rs 10 and an equal number more @ 5 for rs 10.he sells the whole lot at 9 for rs 20.what is his loss or gain % ?
    articles Price
    C.P of 1st batch 4 10
    CP of 2nd batch 5 10
    SP of both batch 9 20
    Taking LCM of articles as 180 we can solve this problem. Let total articles in first batch be 180
    Now, in the first batch, each bundle is of 4 articles...so total bundle = 180/4 = 45 bundles
    Therefore the price of all 180 articles will be Rs 10 x 45 bundles = Rs 450
    Similarly, in 2nd batch, there will be 180/5= 36 bundles and total price will be = 36 x10= Rs 360
    Adding both the batches, the total cost price= 450+360= Rs810
    Now coming on to Selling Price
    Since, there are two batches, therefore total articles sold = 180+180 =360 articles
    each batch is of 9 articles, so total batches sold = 360/9= 40 batches
    Selling Price of each batch is Rs 20, so selling price of all batches will be= Rs 20 x 40 batches = Rs 800
    Clearly SP<CP, therefore, it is loss.
    You can easily calculate it:
    loss %= (C.P.-S.P)/C.P x100= (10/810) x 100 = 100/81% = 1 19/81 % loss
  • 6) a man ordered four pair of black socks.the price of a black sock is double that of a brown pair.while preparing the bill ,the clerk interchanged the no of black & brown sock socks by mistake which increased the bill by 50%.what will be the ratio of black and brown pair in original order?
    Let price of brown pair = Rs 10
    therefore price of black pair = Rs20
    Let number of brown and black socks be respectively x and y
    thus original transaction = 10x+20y
    new transaction by error = 10y+20x
    As per the question, the bill is increased by 50%. Therefore new price will be 150% of the original one
    new transaction= 150% of original
    10y+20x= 150% of (10x+20y)
    y+2x= 3/2 (x+2y)
    2y+4x=3x+6y
    4x-3x=6y-2y
    x=4y
    y/x=1/4
    y:x=1:4
    i.e. number of black socks : number of brown socks= 1:4 <-- answer
  • 4) what will be the minimum value of (x-2) (x-9) ?
    The minimum value will be -6
    If you put x= 0, then then we will get 18. If you put x= 10, then you will get 8. However, if you put a number x between 2 and 9, it will generate negative answer. So one number less than 9 i.e. 8. If we put x=8, then we will get the value as (8-2)(8-9) = -6. This can be the least value formed
    It should be -49/4 (I used differentiation)

    Its not about how much time you have, its what you choose to do with it.
  • 5)a fruit seller buys some oranges @ 4 for rs 10 and an equal number more @ 5 for rs 10.he sells the whole lot at 9 for rs 20.what is his loss or gain % ?
    articles Price
    C.P of 1st batch 4 10
    CP of 2nd batch 5 10
    SP of both batch 9 20
    Taking LCM of articles as 180 we can solve this problem. Let total articles in first batch be 180
    Now, in the first batch, each bundle is of 4 articles...so total bundle = 180/4 = 45 bundles
    Therefore the price of all 180 articles will be Rs 10 x 45 bundles = Rs 450
    Similarly, in 2nd batch, there will be 180/5= 36 bundles and total price will be = 36 x10= Rs 360
    Adding both the batches, the total cost price= 450+360= Rs810
    Now coming on to Selling Price
    Since, there are two batches, therefore total articles sold = 180+180 =360 articles
    each batch is of 9 articles, so total batches sold = 360/9= 40 batches
    Selling Price of each batch is Rs 20, so selling price of all batches will be= Rs 20 x 40 batches = Rs 800
    Clearly SP
    Answer is correct.

    other way of solving-

    since equal no. of oranges are brought so take LCM of 4,5 = 20
    => 20 oranges for 50 rs
    & 20 oranges for 40 rs.
    so CP of 40 oranges= 90 rs => CP of 1 orange=9/4
    a/q SP of 1 orange = 20/9

    so LOSS (9/4>20/9) = (100/81) %
    Its not about how much time you have, its what you choose to do with it.
  • this thread has been made to share your doubts in maths portion and discuss its solutions/shortcuts
    guys do contribute any doubt you encounter or soln to the doubts posted on this thread.senior players are requested to share their tricks
    Can u tell me how to start prepration of ssc
    I have fast airthmetic of rajesh varma
    1 reasoning book
    Objectice eng and normal lewis eng book
  • this thread has been made to share your doubts in maths portion and discuss its solutions/shortcuts
    guys do contribute any doubt you encounter or soln to the doubts posted on this thread.senior players are requested to share their tricks
    Can u tell me how to start prepration of ssc
    I have fast airthmetic of rajesh varma
    1 reasoning book
    Objectice eng and normal lewis eng book
    I ALSO have fast airthmetic of rajesh varma. The question is whether Quantum CAT is useful or not for SSC. Rajesh Verma book has certain limitations.
    Which reasoning book do you have?
  • sarvesh verma is good for its geometry and ci/si/time and work as well as trigonometry,but its not useful for the algebra portion
  • You can join my online course for SSC prep. Please visit csatprep.wordpress.com for more info or PM me.
  • friends, after SSC CGL form completed, and payment....

    when try to take print/view your application then this msg appear....

    Information given by you is incorrect. Please enter the correct information.

    now what i do, and no mail got but amount is deducted ~X( :-w
  • @mods close this thread
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