Answer:
156.06 ft²
Step-by-step explanation:
The applicable formula for the area of the triangle is ...
Area = (1/2)bc·sin(A)
Filling in the given numbers, you have ...
Area = (1/2)(30 ft)(14 ft)·sin(48°) ≈ 156.06041335 ft²
The area of the triangle is about 156.06 square feet.
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Sufficient digits are provided here so that you can round to the precision you (or your computer) may desire.
Answer:
The 90% confidence interval for the population mean iron concentration is between 0.167 cc/m³ and 0.195 cc/m³.
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
Now, find M as such
In which is the standard deviation of the population and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 0.181 - 0.0140 = 0.167 cc/m³.
The upper end of the interval is the sample mean added to M. So it is 0.181 + 0.0140 = 0.195 cc/m³.
The 90% confidence interval for the population mean iron concentration is between 0.167 cc/m³ and 0.195 cc/m³.