A manufacturer of chocolate chips would like to know whether its bag filling machine works correctly at the 423 gram setting. it is believed that the machine is underfilling the bags. A 24 bag sample had a mean of 417 grams with a variance of 196 . A level of significance of 0.05 will be used. Assume the population distribution is approximately normat: State the null and alternative hypotheses.

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\[
\begin{array}{l}
H_{0}: 423 \\
H_{2}: \square
\end{array}
\]

Step 1 ：The manufacturer wants to test if the chocolate chip bag filling machine is underfilling the bags. The machine is set to fill the bags with 423 grams of chocolate chips. A sample of 24 bags is taken and it is found that the mean weight of the bags is 417 grams with a variance of 196 grams. The level of significance for the test is 0.05. The population distribution is assumed to be normal.

Step 2 ：First, we need to state the null and alternative hypotheses. The null hypothesis is that the mean weight of the bags is equal to the setting of the machine, which is 423 grams. This is denoted as \(H_{0}: \mu = 423\).

Step 3 ：The alternative hypothesis is that the mean weight of the bags is less than the setting of the machine, which is 423 grams. This is because it is believed that the machine is underfilling the bags. This is denoted as \(H_{1}: \mu < 423\).

Step 4 ：So, the null and alternative hypotheses are: \[ \boxed{ \begin{array}{l} H_{0}: \mu = 423 \ H_{1}: \mu < 423 \end{array} } \]