Question

If standard deviation of x is 5 then standard deviation of y=2x-3 will be

Answer 1

Answer:

X= 5 let this be equation 1 and

y= 2x-3 be equation 2

put value of X from eq 1 into eq 2

y= 2(5)-3

y=10-3

y=7

Answer 2

Answer:

10

Step-by-step explanation

We can use the formula for the standard deviation of a linear transformation of a random variable to find the standard deviation of y = 2x - 3:

σy = |2|σx = 2σx

where σx is the standard deviation of x.

We are given that σx = 5, so:

σy = 2σx = 2(5) = 10

However, this calculation assumes that the constant term (-3) does not affect the standard deviation. In general, a constant term will not affect the standard deviation of a random variable, but it can affect the mean. If the constant term does affect the standard deviation, we need to use a slightly different formula:

σy = |a|σx

where a is the coefficient of x in the linear transformation.

In this case, a = 2, so:

σy = 2σx = 2(5) = 10

Therefore, the standard deviation of y = 2x - 3 is 10.