Answer:
b = 55 degrees
Step-by-step explanation:
The angles 30, a, b and 45 must sum up to 180 degrees
Subtracting (30 + 45) from both sides leaves us with a + b = 105 degrees.
But b = a + 5. Substituting a + 5 in the equation above yields
a + a + 5 = 105 degrees, so that
2a = 100 degrees, and a = 50 degrees. Then b = a + 5, or b = 55 degrees.
See my steps answer is -12
2. Each side of a pentagon is the same size.
4cm x 5 = 20cm or 4cm+4cm+4cm+4cm+4cm = 20cm
3. Each side of a square is the same size.
13yd x 4 = 52yd or 13yd+13yd+13yd+13yd = 52yd
4. Add all sides together.
12m+12m+30m+30m = 84m
5. Again add all sides together.
16yd+16yd+4yd+4yd = 40yd
6. Each side of a square is the same size.
7in x 4 = 28in. or 7in+7in+7in+7in = 28in
7. Add all sides together.
2cm+2cm+3cm+3cm = 10cm
8. Each side of a rhombus is the same size. A rhombus has 4 sides.
23in x 4 = 92in or 23in+23in+23in+23in = 92in
9. A regular octagon has 8 sides and each side is the same size.
9cm x 8 = 72cm
Answer:
1. Three things influence the margin of error in a confidence interval estimate of a population mean: sample size, variability in the population, and confidence level. For each of these quantities separately, explain briefly what happens to the margin of error as that quantity increases.
Answer: As sample size increases, the margin of error decreases. As the variability in the population increases, the margin of error increases. As the confidence level increases, the margin of error increases. Incidentally, population variability is not something we can usually control, but more meticulous collection of data can reduce the variability in our measurements. The third of these—the relationship between confidence level and margin of error seems contradictory to many students because they are confusing accuracy (confidence level) and precision (margin of error). If you want to be surer of hitting a target with a spotlight, then you make your spotlight bigger.
