IQ scores among the general population have a mean of 100 and a standard deviation of 15. A researcher claims that the standard deviation, 6, of IQ scores for males is less than 15. A random sample of 29 IQ scores for males had a mean of 99 and a standard deviation of 11. Assuming that IQ scores for males are approximately normally distributed, is there significant evidence (at the 0.05 level of significance) to conclude that the researcher's claim is correct? Perform a one-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places and round your answers as specified below. (If necessary, consult a list of formulas.)

IQ scores among the general population have a mean of 100 and a standard deviation of 15. A researcher claims that the standard deviation, 6, of IQ scores for males is less than 15. A random sample of 29 IQ scores for males had a mean of 99 and a standard deviation of 11. Assuming that IQ scores for males are approximately normally distributed, is there significant evidence (at the 0.05 level of significance) to conclude that the researcher's claim is correct? Perform a one-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places and round your answers as specified below. (If necessary, consult a list of formulas.)

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IQ scores among the general population have a mean of 100 and a standard deviation of 15. A researcher claims that the standard deviation,
o, of IQ scores for males is less than 15. A random sample of 29 IQ scores for males had a mean of 99 and a standard deviation of 11.
Assuming that IQ scores for males are approximately normally distributed, is there significant evidence (at the 0.05 level of significance) to
conclude that the researcher's claim is correct?
Perform a one-tailed test. Then complete the parts below.
Carry your intermediate computations to three or more decimal places and round your answers as specified below. (If necessary, consult a list
of formulas.)

(a) State the null hypothesis H, and the alternative hypothesis H .
Ho
H :0
(b) Determine the type of test statistic to use.
|(Choose one) ▼
(c) Find the value of the test statistic. (Round to three or more decimal places.)
(d) Find the critical value. (Round to three or more decimal places.)
(e) Can we support the claim that the standard deviation of IQ scores for males
is less than 15?
O Yes ONo

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