JEE Mains · Maths · STD 11 - 13. statistics
If the mean of the frequency distribution
| Class: | \(0-10\) | \(10-20\) | \(20-30\) | \(30-40\) | \(40-50\) |
| Frequency | \(2\) | \(3\) | \(x\) | \(5\) | \(4\) |
- A \(150\)
- B \(152\)
- C \(153\)
- D \(151\)
Answer & Solution
Correct Answer
(D) \(151\)
Step-by-step Solution
Detailed explanation
Given mean is \(=28\) \(\frac{2 \times 5+3 \times 15+x \times 25+5 \times 35+4 \times 45}{14+x}=28\) \(x =6\) \(\text { Variance }=\left(\frac{\sum x_i^2 f_i}{\sum f_i}\right)-(\text { mean })^2\)…
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