UGC NET
   Top Resources
profile-img
Plabita posted an Question
November 10, 2020 • 14:12 pm 30 points
  • UGC NET
  • English

The average of 35 raw scores is 18.the average of first seventeenth of them is 14 and that of last seventeenth is 20.find the eighteenth raw score.

1 Answer(s) Answer Now
  • 0 Likes
  • 1 Comments
  • 0 Shares
  • comment-profile-img>
    Rishab Soni best-answer

    let 35 raw scores be x1,x2,x3,......,x34,x35 average of 35 raw scores is 18 then [ (x1)+(x2)+(x3)+..….....+(x34)+(x35) ] / 35=18 [ (x1)+(x2)+(x3)+..….....+(x34)+(x35) ]=35(18)=630 (x1)+(x2)+.....+(x17)+(x18)+(x19)+...…....(x34)+(x35)=630......(1) given average of first seventeen of them is 14 then [ (x1)+(x2)+(x3)+......+(x17) ] / 17 =14 [ (x1)+(x2)+(x3)+......+(x17) ]=14(17)=238....(2) given average of last seventeen is 20 then [ (x19)+...…....(x34)+(x35) ] / 17 = 20 [ (x19)+...…....(x34)+(x35) ]=20(17)=340..…..(3) from (1)st,(2)nd, and (3)rd equations we have to substitute the 2nd and 3rd equations values in 1st equation then 238+(x18)+(340)=630 (x18)+578=630 x(18)=630-578=52 therefore,the eighteenth raw score is 52

whatsapp-btn

Do You Want Better RANK in Your Exam?

Start Your Preparations with Eduncle’s FREE Study Material

  • Updated Syllabus, Paper Pattern & Full Exam Details
  • Sample Theory of Most Important Topic
  • Model Test Paper with Detailed Solutions
  • Last 5 Years Question Papers & Answers

Sign Up to Download FREE Study Material Worth Rs. 500/-