A manufacturer of chocolate chips would like to know whether its bag filling machine works correctly at the 404 gram setting. It
is believed that the machine is underfilling the bags. A 27 bag sample had a mean of 402 grams with a variance of 676. A level of significance of 0.1 will be used. Assume the population distribution is approximately normal. Is there sufficient evidence to support the claim that the bags are underfilled?
1 answer:
Answer:
There is no sufficient evidence to support the claim that the bags are underfilled
Step-by-step explanation:
We are given;
n = 27 bags
Sample mean;X = 402 gram
Population mean;μ = 404 gram
Variance = 676
We know that, standard deviation(σ) = √variance
Thus;
σ = √676
σ = 26
The hypotheses are;
Null hypothesis; H0: μ = 404
Alternative hypothesis; HA: μ < 404
Let's find the z-score from the formula;
z = (X - μ)/(√σ/n)
z = (402 - 404)/√(26/27)
z = -2.04
From the z-distribution table attached, we have a p-value of 0.02068
This is less than the significance value of 0.01 and thus we will reject the null hypothesis and conclude that there is no sufficient evidence to support the claim that the bags are underfilled
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Step-by-step explanation:
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