Answer: a) (1008.34,1019.658) b) (1009.24,1018.76)
Step-by-step explanation:
Since we have given that
n = 75
mean = 1014 hours
Standard deviation = 25 hours
At 95% two sided , z = 1.96
So, confidence interval would be
(b) Construct a 95% lower confidence bound on the mean life.
z = 1.65
So, confidence interval would be
Hence, a) (1008.34,1019.658) b) (1009.24,1018.76)
Answer:
44
Step-by-step explanation:
24 divided by 6= 4
2x4=8
3x4=12
24+8+12=44
Answer:
Step-by-step explanation:
∵∛x = (x)^1/3
∴
So you can replace the radicals by fractional exponents
Answer:
The average of all textbooks is $38.60.
Step-by-step explanation:
Here's why to calculate average we do sum of all numbers divided by the number of numbers, for example if we average 2 and 3, we do 2+3 divided by 2. Which happens to be 2.5. Now for this problem we divide the sum by 3.
Therefore getting our answer of $38.60.
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1. First, let us define the width of the rectangle as w and the length as l.
2. Now, given that the length of the rectangle is 6 in. more than the width, we can write this out as:
l = w + 6
3. The formula for the perimeter of a rectangle is P = 2w + 2l. We know that the perimeter of the rectangle in the problem is 24 in. so we can rewrite this as:
24 = 2w + 2l
4. Given that we know that l = w + 6, we can substitute this into the formula for the perimeter above so that we will have only one variable to solve for. Thus:
24 = 2w + 2l
if l = w + 6, then: 24 = 2w + 2(w + 6)
24 = 2w + 2w + 12 (Expand 2(w + 6) )
24 = 4w + 12
12 = 4w (Subtract 12 from each side)
w = 12/4 (Divide each side by 4)
w = 3 in.
5. Now that we know that the width is 3 in., we can substitute this into our formula for length that we found in 2. :
l = w + 6
l = 3 + 6
l = 9 in.
6. Therefor the rectangle has a width of 3 in. and a length of 9 in.