The null hypothesis should have a statement of equality. Another way of thinking of it is that the null hypothesis is a statement of "no difference."

In this context, Marta's null hypothesis should be that the mean birth weight in this nation is no different than the reported value. In other words, she should assume that the mean birth weight is equal to 3.5 kg

H_{0}: the mean birth weight in this nation is equal to** 3.5 kg,** is the answer.

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**Hypothesis Test** for a **Population Mean** (5 of 5) | Concepts in **Statistics**

This year, a random **sample** of 50 **babies** has a **mean weight** of about 3,400 grams with a standard deviation of about 500 grams. Here is the distribution of **birth** ...

For more information, see **Hypothesis Test** for a **Population Mean** (5 of 5) | Concepts in **Statistics**