C) $20
40 divided by 30 is 1.3
1.3 times 15 is 30
Answer:
405
Step-by-step explanation:
To find sample size, use the following equation, where n = sample size, za/2 = the critical value, p = probability of success, q = probability of failure, and E = margin of error.

The values that are given are p = 0.84 and E = 0.03.
You can solve for the critical value which is equal to the z-score of (1 - confidence level)/2. Use the calculator function of invNorm to find the z-score. The value will given with a negative sign, but you can ignore that.
(1 - 0.9) = 0.1/2 = 0.05
invNorm(0.05, 0, 1) = 1.645
You can also solve for q which is 1 - p. For this problem q = 1 - 0.84 = 0.16
Plug the values into the equation and solve for n.

Round up to the next number, giving you 405.
Answer:
i think the difference in height from the top to the bottom is 8ft
Answer:
Step-by-step explanation:
2x+5y=12
3x+4y=11
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3(2x+5y)=3(12)
-2(3x+4y)=-2(11)
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6x+15y=36
-6x-8y=-22
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7y=14
y=14/7=2
2x+5(2)=12
2x+10=12
2x=12-10=2
x=2/2=1
x=1, y=2. (1, 2)
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I just provided you an example of a system of equations and I already solved it for you.
Answer: 6
Step-by-step explanation:
They are similar triangles so they have proportionality
For the small triangle the side is 2 and the hypoteneuse is 4, for the large triangle the side is 5 so the entire hypoteneuse is 10. 10-4 = 6 which is the missing side