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c. The percentage of hippos born weighing 25 pounds or less is(Round to one decimal place as needed.)

c. The percentage of hippos born weighing 25 pounds or less is(Round to one decimal-example-1
User Jimmy Pitts
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1 Answer

8 votes
8 votes

Given data:

Mean: 84 lb

Standard deviation: 12lb

Find % of hippos born weighing 25 poind or less.

1. Find the z-score corresponding to x=25:


\begin{gathered} z=(x-\mu)/(\sigma) \\ \\ z=(25-84)/(12) \\ \\ z=-(59)/(12) \\ \\ z=-4.92 \end{gathered}

2. Use a z-table to find the probability of x less or equal to 25 (z-score -4.92):

For a z-score of -3.50 or less the corresponding value is 0.0001


P(x\leq25)=0.0001

3. Multiply by 100 the value you get in step 2 to get the percentage:


0.0001*100=0.01Then, the percentaje of hippos born weighing 25 poind or less is 0.01%
User Michael Douma
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