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According twhat amourThe graph shows the distribution of the amount ofchicken (in ounces) that adults eat in one sitting. Thedistribution is approximately Normal, with a mean of 8ounces and a standard deviation of 1.2 ounces.O 4.4 ounc不O 5.6 ouncChicken Consumption0 10.4 oundO 11.6 ounc

According twhat amourThe graph shows the distribution of the amount ofchicken (in-example-1
According twhat amourThe graph shows the distribution of the amount ofchicken (in-example-1
According twhat amourThe graph shows the distribution of the amount ofchicken (in-example-2
User Anjana Silva
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1 Answer

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To answer this question, we can proceed as follows:

1. We have a normal distribution with a mean, μ = 8 ounces, and a standard deviation, σ = 1.2 ounces.

2. We need to determine the value, x, in the distribution for which the cumulative probability is less than 2.5%.

3. To do this, we can use the z-scores, and they are defined as:


z=(x-\mu)/(\sigma)

And we already know that:

• μ = 8 ounces

,

• σ = 1.2 ounces

4. If we consult the cumulative standard normal distribution table, we need to find the corresponding value for z for a cumulative probability of 2.5%. Then we have:


P(z<-1.96)=0.025

Therefore, we have the corresponding value of z for a cumulative probability of 2.5% (=2.5/100) is z = -1.96.

5. Now, to find the value of x, we can proceed as follows:


\begin{gathered} z=(x-\mu)/(\sigma) \\ \\ -1.96=(x-8)/(1.2) \end{gathered}

6. Multiply both sides of the equation by 1.2:


(1.2)(-1.96)=x-8

7. And now add 8 to both sides of the equation:


\begin{gathered} (1.2)(-1.96)+8=x \\ \\ \\ x=(1.2)(-1.96)+8 \\ x=5.648 \end{gathered}

If we round the result to the nearest tenth, we have x = 5.6 ounces.

And we can see that in the following graph:

Therefore, according to the graph, 2.5% of adults eat less than 5.6 ounces of chicken in one sitting (second option).

According twhat amourThe graph shows the distribution of the amount ofchicken (in-example-1
User Robert Metzger
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