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The monthly income, X, of a family in a given city is normally distributed with mean $3000 and

standard deviation $500. Use this information to find

34.

A) 0.9974 B) 0.4987 C) 0.5601 D) 0.0013

35. The probability that a person selected at random earns a monthly income between $2500 and $

3500

A) 0.3174 B) 0.3413 C) 0.6826 D) 0.1587

Let X be a normally distributed random variable with mean 100 and a standard deviation 10. Use

this information to find the value of a in the following two questions such that

36. P (95 < X < a) = 0.6309

A) 101.5 B) 15.5 C) 115.5 D) 84.5

37. P (X > a) = 0.0427

A) 82.8 B) 117.2 C) 101.72 D) 17.2