The confidence interval formula is computed by:
Xbar ± Z s/ sqrt (n)
Where:
Xbar is the mean
Z is the z value
S is the standard deviation
N is the number of samples
So our given are:
90% confidence interval with a z value of 1.645
Sample size 40, 45
Mean 180, 179
Standard deviation 2, 4
So plugging that information in the data will give us a
confidence interval:
For 1:
Xbar ± Z s/ sqrt (n)
= 180 ± 1.645 (2 / sqrt (40))
= 180 ± 1.645 (0.316227766)
= 180 ± 0.520194675
= 179.48, 180.52
For 2:
Xbar ± Z s/ sqrt (n)
= 179 ± 1.645 (4 / sqrt (45))
<span>= 179 ± 1.645 (0.596284794)</span>
therefore, the answer is letter b
Answer:
5(2x - 1)
Step-by-step explanation:
Given
2(x - 6) + 4(2x + 1) + 3 ← distribute both parenthesis
= 2x - 12 + 8x + 4 + 3 ← collect like terms
= (2x + 8x) + (- 12 + 4 + 3)
= 10x + (- 5)
= 10x - 5 ← factor out 5 from each term
= 5(2x - 1) ← in factored form
Answer:
120
Step-by-step explanation:
area = 15 x 8
It's the1st: 4 cm/10 cm because:
4/10 = 2/5 . and because they have the SAME UNIT (cm)
Answer:
x=32/7
Step-by-step explanation:
7x-2(1)=30 Plug in 1 as y and simplify.
7x-2=30 Add 2 on both sides of the equation.
<u>+2 +2</u>
7x=32 Divide both sides of the equation by 7.
<u>/7 /7</u>
x=32/7
Hope this helps...have an amazing day (｡･∀･)ﾉﾞ
