Answer:
The sample size needed to be taken is approximately 74.
Step-by-step explanation:
To get alpha; we have 1 - 0.95 = 0.05
Therefore,
The we look up z* in a Standard Normal table where α = 0.025 area in each tail.
From the table, z* = 1.96
From the question variance is 484, then the standard deviation is 22
Standard deviation =
And margin of error is 5 or less
The formula for margin of error is given as:
margin of error =
The approximate value of n is 74.
Answer:
Step-by-step explanation:
It is given that,
Length of each brick = 10 inches
Mortar between between each brick = 1 inch
For 2 bricks, we need mortar once.
For 3 bricks, we need mortar 2 times.
For 4 bricks, we need mortar 3 times.
Similarly,
For n bricks, we need mortar (n-1) times.
Total length of n bricks = 10n inches
Total length of (n-1) times mortar = 1(n-1) = n-1 inches
Total length of wall = 10n + (n-1) inches.
1 feet = 12 inches
10 feet = 120 inches
The equation to model the number of bricks,n, nikki needs in each layer to build a wall 10 feet long.
Therefore, the required equation is .