Question

Find the standard deviation of 40 42 48 .If each value is multiplied by 3.Find the standard deviation of the new data

Answer 1

Answer:

Step-by-step explanation:

X Y  Mean(u) (x-u)          (x-u)^2

1 40 43.3  -42.3 1792.11

2 42          -41.3 1708.44

3 48          -40.3 1626.77

standard Deviation = $\sqrt{\frac{1792.1+1708.4+1626.7}{3} }$;

Standard Deviation  = 41.34;

Now multiplying 3 in each numbers;

X Y  Mean(u) (x-u)         (x-u)^2

1 120   130 -129        16641

2 126          -128         16384

3 144           -127 16129

standard deviation  = 128.00