The correct answer that you are looking for is C ( 75,000).
You need to know the slope and the y intercept
Answer:
Sample mean = 7.1
Margin of error = 0.465
Step-by-step explanation:
Formula for confidence interval is;
CI = x¯ ± zE
Where;
x¯ is sample mean
z is critical value at confidence level
E is margin of error.
z for 99% Cl is 2.58
We are told the CI is 5.9 to 8.3.
Thus;
5.9 = x¯ - 2.58E - - - - (1)
8.3 = x¯ + 2.58E - - - - (2)
Add both equations together to get;
14.2 = 2x¯
x¯ = 14.2/2
x¯ = 7.1
Put 7.1 for x¯ in eq 1 to get;
5.9 = 7.1 - 2.58E
7.1 - 5.9 = 2.58E
E = 1.2/2.58
E = 0.465
Answer:
a battery costs £0.43
Step-by-step explanation:
<u>Set up an equation</u>
11b+b+4.84=10
S<u>ubtract 4.84 from both sides</u>
12b+4.84=10
-4.84=-4.84
12b=5.16
<u>Divide 12 on both sides</u>
b=5.16/12
b=0.43
