JEE Mains · Maths · STD 11 - 13. statistics
Consider the following frequency distribution :
| Class: | \(0-6\) | \(6-12\) | \(12-18\) | \(18-24\) | \(24-30\) |
| Frequency : | \(a\) | \(b\) | \(12\) | \(9\) | \(5\) |
- A \(5\)
- B \(6\)
- C \(7\)
- D \(11\)
Answer & Solution
Correct Answer
(C) \(7\)
Step-by-step Solution
Detailed explanation
Class Frequency \(X_i\) \(F_i\,X_i\) \(0-6\) \(a\) \(3\) \(3a\) \(6-12\) \(b\) \(9\) \(9b\) \(12-18\) \(12\) \(15\) \(180\) \(18-24\) \(9\) \(21\) \(189\) \(24-30\) \(5\) \(27\) \(135\) \(N=(26+a+b)\) \((504+3a+9b)\) Mean \(=\frac{3 a+9 b+180+189+135}{a+b+26}=\frac{309}{22}\)…
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