JEE Mains · Maths · STD 11 - 13. statistics
The frequency distribution of the age of students in a class of \(40\) students is given below.
| Age | \(15\) | \(16\) | \(17\) | \(18\) | \(19\) | \(20\) |
| No. of students | \(5\) | \(8\) | \(5\) | \(12\) | \(X\) | \(Y\) |
- A \(43\)
- B \(44\)
- C \(47\)
- D \(46\)
Answer & Solution
Correct Answer
(B) \(44\)
Step-by-step Solution
Detailed explanation
\( \mathrm{x}+\mathrm{y}=10 \ldots \ldots \ldots(1) \) \( \text { Median }=18=\mathrm{M} \) \( \text { M.D. }=\frac{\sum \mathrm{f}_{\mathrm{i}}\left|\mathrm{x}_{\mathrm{i}}-\mathrm{M}\right|}{\sum \mathrm{f}_{\mathrm{i}}} \) \( 1.25=\frac{36+\mathrm{x}+2 \mathrm{y}}{40} \)…
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