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The geowall team measured the strength of paper strips by applying a force until they broke. They tested 5 strips and found an average strength of 12.9 pounds with a standard deviation of 1 pound. Because of the small sample size, we cannot assume a normal distribution. What is the probability that a strip breaks with only 11 pounds of applied force? (a) 0.065 (b) 0.029 (c) 1.07 × 10?5 (d) 0.058 (e) none of the above

User Ghik
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1 Answer

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Answer:

Explanation:

Given

mean
\mu =12.9 Pounds

Standard deviation
\sigma =1\ Pound


P(x<11)=P\left ( (x-\mu )/(\sigma )< (11-12.9)/(1)\right )


P(x<11)=P\left ( z< -1.9\right )

From z table


P(x<11)=0.0289\approx 0.029

User Dephinera
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