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The frequency distribution of the age of students in a class of 40 students is given below. array |l|c|c|c|c|l|l| Age & 15 & 16 & 17 & 18 & 19 & 20 No of Students & 5 & 8 & 5 & 12 & x & y array If the mean deviation about the median is 1.25, then 4 x+5 y is equal to :

Options

  1. A46
  2. B43
  3. C44
  4. D47

Correct answer

C. 44

Step-by-step solution

aligned & x + y =10 .(1) & Median =18= M & M.D. = f _ i | x _ i - M | f _ i & 1.25= 36+ x +2 y 40 & x +2 y =14 .(2) & by (1) & (2) & x =6, y =4 & 4 x +5 y =24+20=44 aligned array |l|l|l|l| Age ( x _ i ) & f & | x _ i - M | & f _ i | x _ i - M | 15 & 5 & 3 & 15 16 & 8 & 2 & 16 17 & 5 & 1 & 5 18 & 12 & 0 & 0 19 & x & 1 & x 20 & y & 2 & 2 y array

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