Suppose the value of Young's modulus (GPa) was determined for
cast plates consisting of certain intermetallic substrates,
resulting in the following sample observations:
116.7 115.8 114.5 115.1 115.5
(a) Calculate x.
GPa
Calculate the deviations from the mean. (Enter your answers to
two decimal places.)
x 116.7 115.8 114.5 115.1 115.5
deviation ____ , ______, ______, ______, _______
(b) Use the deviations calculated in part (a) to obtain the
sample variance and the sample standard deviation. (Round your
answers to three decimal places.)
s2 = GPa2
s = GPa
(c) Calculate s2 by using the computational formula for the
numerator Sxx. (Round your answer to three decimal places.)
GPa2
(d) Subtract 100 from each observation to obtain a sample of
transformed values. Now calculate the sample variance of these
transformed values. (Round your answer to three decimal
places.)
GPa2
Compare it to s2 for the original data.
The variance in part (d) is greater than the variance in part
(b).
The variance in part (d) is equal to the variance in part
(b).
The variance in part (d) is smaller than the variance in part
(b).