Question

Use the following information to answer problems 14-16: Suppose that in a large metropolitan area, 82% of all households have cable tv. Suppose you are interested in selecting a group of six households from this area. Let X be the number of households in a group of six households from this area that have cable tv. For what proportion of groups will exactly four of the six households have cable tv?

Answer 1

66.6% or 0.66

Explanation:

82% or 0.82 of All households have cable TV.

X = The number of households in a group of 6, that have cable TV.

You wish to find the proportion or percentage of groups for which EXACTLY 4 of 6 households will have cable TV.

82% of 6 is = 4.92

Approximately 4.92 out of 6 households, have cable TV.

Using this figure, you can now find out what % of 6 will give you 4.

Cross multiply:

0.82 - 4.92

M - 4

M = (4×0.82) ÷ 4.92 = 3.28÷4.92 = 0.666

Hence, 66.6% of 6 households, have cable TV. In other words, exactly 4 households (X=4) have cable TV.

To test, you can find what 66% of 6 is. You will get 4.