Using the quadratic formula works but if you know there are 2 answers (highest power of problem tells you how many solutions) then
10x^2 = 5x
So either x = 0, giving 0=0. Or divide by 5x
2x = 1
x = 0.5

8 0

3 years ago

Molybdenum rods are produced by a production line setup. It is desirable to check whether the process is in control, i.e. equal

ikadub [295]

Answer: Test statistic = -8 and rejected region is (-∞,-1.966) and (1.966, ∞)

Step-by-step explanation:

Since we have given that

X is the length of a rod.

Sample Mean = 2 inches

Standard deviation = 0.5 inches

n = 400

Hypothesis are

$H_0:\mu=2.2\\\\H_1:\mu\neq 2.2$

Test statistics would be

$t=\dfrac{\bar{x}-\mu}{\dfrac{\sigma}{\sqrt{n}}}}\\\\t=\dfrac{2-2.2}{\dfrac{0.5}{\sqrt{400}}}\\\\t=-8$

Degrees of freedom = n-1 =400-1 =39

and $\alpha =0.05\\\\\dfrac{\alpha }{2}=\dfrac{0.05}{2}=0.025$

Using the t-distribution table, we get that critical value z = 1.966

Since the two tail test will be applied to this,

So, the acceptance region will be (-1.966, 1.966)

Hence, the rejected region will be (-∞,-1.966) and (1.966, ∞)

5 0

3 years ago