SOLUTION: Could someone help me to understand how you get the answer to the problems leisted. I have it to a point but I get stuck. 1. If the random variable z is the standard normal

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Question 364556: Could someone help me to understand how you get the answer to the problems leisted. I have it to a point but I get stuck.

1. If the random variable z is the standard normal score, is it true that P(-3 < z < 3) > 1? Why or why not?

2. Givent a binomial distribution with n = 29 and p = 0.83, would the normal distribution provide a reasonable approximation? Why or why not?

3. Find the area under the standard normal curve for the following: a). P(z < -0.25) b). P(0.55 < z < 0) c.) P(-1.91 < z < 1.06)
Found 2 solutions by Fombitz, stanbon:
Answer by Fombitz(32388) (Show Source):
You can put this solution on YOUR website!
DUPLICATE See Probability-and-statistics/364479:

Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
1. If the random variable z is the standard normal score, is it true that P(-3 < z < 3) > 1? Why or why not?
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No. Maximum area under the normal curve is +1. No probability
can exceed +1.
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2. Given a binomial distribution with n = 29 and p = 0.83, would the normal distribution provide a reasonable approximation? Why or why not?
np = 24
nq = 4.93
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Since nq is not > 5 the normal approx should not be used
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3. Find the area under the standard normal curve for the following:
a). P(z < -0.25) = normalcdf(-100,-0.25) = 0.4013
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b). P(0.55 < z < 0)
Note: Your inequality is backward.
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c.) P(-1.91 < z < 1.06) = normalcdf(-1.91<1.06) = 0.8274
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Cheers,
Stan H.