Loading ...
Sorry, an error occurred while loading the content.

pls solve them...

Expand Messages
  • shruti bhagi
    hi pls help me in solving these problems.. 1. how many 3 digit no.s r there which when divided by 7 or 8 gives a remainder of 4 in each case? 2. what is the
    Message 1 of 5 , Jun 16, 2006
    • 0 Attachment
      hi pls help me in solving these problems..
       
      1. how many 3 digit no.s r there which when divided by 7 or 8 gives a remainder of 4 in each case?
       
      2. what is the sum of all the numbers formed by taking each of the digits 2,3,5,6 and 8 once?
       
      3.fresh mango contains 70% water by weight whereas dry mango contains 10% water by weight. what is the weight of dry mango that can b obtained from 20 kg of fresh mango?
      a. 6.66kg
      b. 6 kg
      c. 6.84 kg
      d. cannot b determined
       
      4. starting with 1, positive integers are written one after the other. what is the 40000th digit that will be written?
      a. 2
      b. 4
      c. 3
      d. 1


      Sneak preview the all-new Yahoo.com. It's not radically different. Just radically better.
    • kshitiz garg
      Ans 1 . Such a no. will be LCM(7,8)*K + 4 where K is a +ve integer i.e. 56K + 4 so for 3 digits 1
      Message 2 of 5 , Jul 2, 2006
      • 0 Attachment
        Ans 1 .
        Such a no. will be LCM(7,8)*K + 4  where K is a +ve integer
        i.e. 56K + 4
        so for 3 digits  1<K<18
        16 values of K are possible . Hence 16 such nos.....

        Ans 2.
        there will be 5*4*3*2*1 = 120  nos. that can be formed with these 5 digits....
        lets consider the no. which end with '1'.....
        ie. fix '1' at the end so there are 4! such nos.....similarly for 2,3,4,5....
        hence the sum of the unit's digits of these nos ....
        24*(1+2+3+4+5)
        the sum of the ten's digits of these nos ....
        24*(1+2+3+4+5)*10
        the sum of the hundred's digits of these nos ....
        24*(1+2+3+4+5)*100
        the sum of the thousand's digits of these nos ....
        24*(1+2+3+4+5)*1000
        the sum of the ten thousand's digits of these nos ....
        24*(1+2+3+4+5)*10000
        total sum = 24 * (1+2+3+4+5)* (10000+1000+100+10+1)
        = 24 * (1+2+3+4+5)* (11111)
        = 24 * (15)* (11111)
        = 4! * (15)* (11111)
        so, in general , we have a formula for this type of questions ....
        ie. SUM = (total digits-1)! * (sum of digits) * (1111.......)
        where no. of 1's = total digits

        Ans 3.
        20 kg of fresh mango ---> 6 Kg net mango :)
        so to contain this much net mango
        we get to know that 6kg should be 90% of the dry mango...
        so .9X = 6
        X = 6.66

        Ans. 4
        m workin on it :)

        shruti bhagi <shruti_bhagi@...> wrote:
        hi pls help me in solving these problems..
         
        1. how many 3 digit no.s r there which when divided by 7 or 8 gives a remainder of 4 in each case?
         
        2. what is the sum of all the numbers formed by taking each of the digits 2,3,5,6 and 8 once?
         
        3.fresh mango contains 70% water by weight whereas dry mango contains 10% water by weight. what is the weight of dry mango that can b obtained from 20 kg of fresh mango?
        a. 6.66kg
        b. 6 kg
        c. 6.84 kg
        d. cannot b determined
         
        4. starting with 1, positive integers are written one after the other. what is the 40000th digit that will be written?
        a. 2
        b. 4
        c. 3
        d. 1

        Sneak preview the all-new Yahoo.com. It's not radically different. Just radically better.


        Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1ยข/min.

      • Nibedita Moitra
        soln 1 ... 3 digit nos which divided by 7 leaves remainder four is 7x+4 where x=14 to 142 so total (142-14)+1 nos=129 3 digit nos which divided by 8 leaves
        Message 3 of 5 , Jul 3, 2006
        • 0 Attachment
          soln 1
          ---------------------------------------
          3 digit nos which divided by 7 leaves remainder four is 7x+4 where x=14 to 142 so  total (142-14)+1 nos=129
          3 digit nos which divided by 8 leaves remainder four is 8x+4 where x=12 to 124
          so total (124-12)+1nos=113
           
          so total no of nos is=129+113=242
          but there r nos that when divided by both 7 n 8 leave reamainder 4. We have counted thse nos twice
           
          these nos rof the form 56x+4 where x=2 to 17 total 17-2+1 nos=16
          So actual no of 3 digit nos =242-16=226
           
          soln 2
          -------------------------
          its a very standard problem u can get in any XI th standard maths book
           
          soln 4
          ---------------------------------------
          Digits contributed by 1 digit nos=1*9
          Digits contributed by  2 digit nos=2*90
          Digits contributed by 3 digit nos=3*900
          .
          .
          .
          .
          Digits contributed by n digit nos=n*9*10^(n-1)
          ----------------------------------------------------------------
          Total no of digits= n*10^n- (10^n-1)/9
          putting n=4
          we find total no of digits upto all 4 digit nos is 38,889
          No of digits after 4 digit nos and 40,000 th digit is
          1111
          all r contributed by 5 digit nos
          there r 200 5 digit nos
          so 40,000th digit is the staring digit of 10200 i.e 1
           
          Ans (d)



          shruti bhagi <shruti_bhagi@...> wrote:
          hi pls help me in solving these problems..
           
          1. how many 3 digit no.s r there which when divided by 7 or 8 gives a remainder of 4 in each case?
           
          2. what is the sum of all the numbers formed by taking each of the digits 2,3,5,6 and 8 once?
           
          3.fresh mango contains 70% water by weight whereas dry mango contains 10% water by weight. what is the weight of dry mango that can b obtained from 20 kg of fresh mango?
          a. 6.66kg
          b. 6 kg
          c. 6.84 kg
          d. cannot b determined
           
          4. starting with 1, positive integers are written one after the other. what is the 40000th digit that will be written?
          a. 2
          b. 4
          c. 3
          d. 1

          Sneak preview the all-new Yahoo.com. It's not radically different. Just radically better.



          With Best Wishes
          Nibedita Moitra


          Yahoo! India Answers: Share what you know. Learn something new Click here
          Catch all the FIFA World Cup 2006 action on Yahoo! India Click here

        • anshugoswamy
          answer to the 1st question: there are 16 numbers. solution: to find least no. which when divided by 7 and 8 leaves remainder 4 in each case, find lcm of 7 and
          Message 4 of 5 , Jul 8, 2006
          • 0 Attachment
            answer to the 1st question:

            there are 16 numbers.
            solution:

            to find least no. which when divided by 7 and 8 leaves remainder 4 in
            each case, find lcm of 7 and 8 and add 4 to it i.e. (lcm of 7 & 8 )+
            4.

            but we need 3 digit nos.
            so lcm of 7 nd 8 is 56. the lowest three digit multiple of 56 is 112
            (56*2).
            therefore, the first three digit number which gives 4 when divided by
            either 7 or 8 is 112+4 i.e. 116.

            similarly the highest three digit no. fulfilling the condition would
            be the highest three digit multiple of 56 + 4.
            the highest three digit no. which is a multiple of 56 is 952 (to find
            out divide 1000 by 56 which gives 17.something. so 17*56 will be the
            highest three digit multiple of 56.)

            so 952+4 = 956 is the highest three digit number fulfilling the
            criteria.

            therefore by A.P. a+(n-1)d = L
            now, L=952
            a=116
            d=56

            hence, n=16.

            --- In ascent4cat@yahoogroups.com, shruti bhagi <shruti_bhagi@...>
            wrote:
            >
            > hi pls help me in solving these problems..
            >
            > 1. how many 3 digit no.s r there which when divided by 7 or 8
            gives a remainder of 4 in each case?
            >
            > 2. what is the sum of all the numbers formed by taking each of
            the digits 2,3,5,6 and 8 once?
            >
            > 3.fresh mango contains 70% water by weight whereas dry mango
            contains 10% water by weight. what is the weight of dry mango that
            can b obtained from 20 kg of fresh mango?
            > a. 6.66kg
            > b. 6 kg
            > c. 6.84 kg
            > d. cannot b determined
            >
            > 4. starting with 1, positive integers are written one after the
            other. what is the 40000th digit that will be written?
            > a. 2
            > b. 4
            > c. 3
            > d. 1
            >
            >
            > ---------------------------------
            > Sneak preview the all-new Yahoo.com. It's not radically different.
            Just radically better.
            >
          • Pritish.K. Devassy
            ... the answer s 1.. coz u see that there are 9 1 digit numbers and 90 2 digit numbers and 900 three digit nums.. so keep on going .. ull end up as 1.. hey can
            Message 5 of 5 , Jul 17, 2006
            • 0 Attachment
              >
              > 4. starting with 1, positive integers are written
              > one after the other. what is the 40000th digit that
              > will be written?
              > a. 2
              > b. 4
              > c. 3
              > d. 1
              >

              the answer s 1.. coz u see that there are 9 1 digit
              numbers and 90 2 digit numbers and 900 three digit
              nums.. so keep on going .. ull end up as 1..



              hey can anyone tell me how to improve english grammar
              and RCS...

              __________________________________________________
              Do You Yahoo!?
              Tired of spam? Yahoo! Mail has the best spam protection around
              http://mail.yahoo.com
            Your message has been successfully submitted and would be delivered to recipients shortly.