Statistics for Business: Decision Making and Analysis, 3rd Edition

Think About It

1. 21.

   1. [4.983 kg to 20.385 kg]

   2. [¥267,490 to ¥511,720]

   3. [$54.5 to $76.44]

   4. [$18,600 to $29,160] per store

2. 23. ½, assuming the sample size condition holds.

3. 25. Cannot tell unless you know σ. If σ = s, the t- interval is longer because z_α < t_{α,n − 1} If s < σ, the t-interval may be shorter.

4. 27.

   1. We are 95% confident that the mean height of men who visit this store lies between about 70.9 and 74.5 inches.

   2. ≈ 1.8 inches.

   3. Probably to the nearest inch.

   4. Longer.

5. 29. The population average of sales is within $15 of the estimate, with some degree of confidence.

6. 31.

   1. 625 using z = 2. If z = 1.96, then n = 600.

   2. ≈ 400

7. 33.

   1. PD × EAD × LGD = $3,000

   2. 0.05 × 220000 × 0.18 = $1,980 to 0.07 × 290000 × 0.23 = $4,669

   3. The product has coverage at least 1 ...