Suppose that among gifted seventh-graders who score very high on a mathematics exam, app...

Suppose that among gifted seventh-graders who score very high on a mathematics exam, approximately 20% are left-handed or ambidextrous. Let X equal the number of left-handed or ambidextrous students among a random sample of n = 25 gifted seventh-graders. Find P(2 < X < 9)

(a) Using Table II in Appendix B.

(b) Approximately, using the central limit theorem.

REMARK Since X has a skewed distribution, the approximation is not as good as that for the symmetrical distribution where p = 0.50, even though np = 5.