JEE Mains · Maths · STD 11 - 13. statistics
Let the mean and the standard deviation of the observation \(2,3,3,4,5,7\), a, b be 4 and \(\sqrt{2}\) respectively. Then the mean deviation about the mode of these observations is :
- A \(1\)
- B \(\frac{3}{4}\)
- C \(2\)
- D \(\frac{1}{2}\)
Answer & Solution
Correct Answer
(A) \(1\)
Step-by-step Solution
Detailed explanation
\begin{aligned} & \frac{24+a+b}{8}=4 \\ & a+b=8 \\ & 2=\frac{4+1+1+0+1+9+(a-4)^2+(b-4)^2}{8} \\ & 16=48+a^2+b^2-8 a-8 b \\ & a^2+b^2=32 \\ & 32=2 a b \\ & a b=16 \\ & a=4 b=4 \\ & \text { mode }=4 \\ & \text { mean deviation }=\frac{2+1+1+0+1+3+0+0}{8}=1 \\ & \text { option…
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