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Let x1, x2, ,xn be xn observations. Let ...

Let `x_1, x_2, ,x_n` be `x_n` observations. Let `y_i=a x_i+bfori=1,2, ,nw h e r eaa n db` are constants. If the mean of `xi ' s` is 48 and their standard deviation is 12, the mean of `y i ' s` is 55 and standard deviation of `y i ' s` is 15, the values of a and b are `a=1. 25 ,b=-5` (b) `a=-1. 25 ,b=5` \ (c) `a=2. 5 ,b=-5` (d) `a=2. 5 ,b=5`

A

`a=1.25, b = -5`

B

`a=-1.25,b=5`

C

`a=2.5,b=-5`

D

`a=2.5,b=5`

Text Solution

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The correct Answer is:
A
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