5. Past experience shows that the standard deviation of the distances traveled by consumers to patronize Chinese restaurants is 2 km. How large a sample is needed to estimate the population mean distance traveled to within 0.4 km

96

Step-by-step explanation:

Given that :

Standard deviation (s) = 2km

Error in estimation is within 0.4 km ; Error (E) = 0.4 km

Using the relation :

Sample size = ((Zα/2 * s) /E)^2

Using α = 0.05

The Zcritical at 0.05 = Z0.025 = 1.96

Sample size = ((1.96 * 2) / 0.4)^2

Sample size = (3.92 / 0.4)^2

Sample size = 9.8²

Sample size = 96.04

Required sample size = 96

14 ft 7 inches

step-by-step explanation:

since each model inch corresponds to 25 real inches, 7 model inches will correspond to

7×25" = 175"

at 12" per foot, that is 14 feet, 7 inches.

x=-7

step-by-step explanation:

x+3=-10

-10+3=-7

x=-7