ExamBro
ExamBro
AP EAMCET · Maths · Statistics

The mean of the numbers \(a, b, 8,5\) and 10 is 6 and the variance is 6.80 , then the possible values of \(a\) and \(b\) are

  1. A \(a=2, b=3\)
  2. B \(a=4, b=5\)
  3. C \(a=1, b=3\)
  4. D \(a=3, b=4\)
Verified Solution

Answer & Solution

Correct Answer

(D) \(a=3, b=4\)

Step-by-step Solution

Detailed explanation

Given data, \(a, b, 8,5,10\) \(\therefore \quad\) Mean \(=\frac{a+b+8+5+10}{5}\) \(6=\frac{a+b+23}{5}\) \(\Rightarrow \quad a+b=7\) ...(i) Variance \(=\frac{(a-6)^2+(b-6)^2+(8-6)^2+(5-6)^2+(10-6)^2}{5}\) \(\Rightarrow 6.80=\frac{a^2+36-12 a+b^2+36-12 b+4+1+16}{5}\)…