Answer:
The critical value for the 95% confidence interval is z = 1.96.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of 
So it is z with a pvalue of
, so z = 1.96.
The critical value for the 95% confidence interval is z = 1.96.
Answer:
The error with mark’s work is that a negative times a negative will give a positive. So -3 times -5 is +15 not -15. Then 15 times -2 will get you -30.
Answer:
40 pounds costs $32!!!
Step-by-step explanation:
Answer:
1. 55.271 inches/lb
2. 3.075 inches/lb
3. The denser one is the pine, so it would be heavier.
Step-by-step explanation:
1. density of the pine log (which is a cylinder)
We need the weight/mass and the volume.
V(cylinder) = πr^2 * height
= πr^2 = π(5^2) = 25π = 78.54
= 78.54 * 30 = <u>2356 cubic inches</u>
The weight is 42.63.
Density = mass/volume = 2356/42.63 = <u>55.271 inches/lb</u>
2. density of the oak board (which is a rectangular prism)
We need the weight/mass and the volume.
V(prism) = l*w*h
= 5.5*1.5*3 = <u>24.75 cubic inches</u>
The weight is 8.05.
Density = mass/volume = 24.75/8.05 = <u>3.075 inches/lb</u>
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3. Picture a box made out of stone and a box made out of cardboard. Same dimensions, but the stone one would be way heavier because stone is denser.
The answer is a. (0,2) , (1,2), (2,3), (1,4) , (3,1)
this is because (x, y) . x is first then y