Answer:
2.897
Step-by-step explanation:
Let us find the mean and variance for the sample first.
105 104 110 112
114 106 108 109
Mean = sum/8 = 108.5
Variance = 12
Std dev = sq rt of variance = 3.464
Std error = std dev/ sq rt n
since n =8, we get std error = 1.225
Since sample size is small, df =8-1 =7
For 95% confidence intervals, t critical value for two tailed=2.365
Margin of error = std error x t critical = 1.225(2.365)
=2.897
V=pir^2(h/3)
V= 3.14x18^2x6/3
V= about <span>2034.72</span>
Answer:
Question 2
Step-by-step explanation:
2) The time when she woke up was - 3° C
During nature walk, temperature got 3° C warmer than when she woke up.
So, temperature during nature walk = - 3 + 3 = 0° C
Answer:
17
Step-by-step explanation:
You have to plug -2 into every x in the function, so:
(-2)^2 - 3 (-2) + 7
4 + 6 + 7
17
<h3>
Answer: 80 meters</h3>
This is an isosceles triangle. The dashed line is the height which is perpendicular to the base 120. The height is always perpendicular to the base. The dashed line cuts the base into two equal pieces (this only works for isosceles triangles when you cut at the vertex like this).
So we have two smaller triangles each with a base of 60 and a height of x. Focus on one of the right triangles and use the pythagorean theorem to solve for x.
a^2 + b^2 = c^2
x^2 + (60)^2 = (100)^2
x^2 + 3600 = 10000
x^2 = 10000 - 3600
x^2 = 6400
x = sqrt(6400)
x = 80
Each smaller right triangle has side lengths of 60, 80, 100
Note the ratio 60:80:100 reduces to 3:4:5. A 3-4-5 right triangle is a very common pythagorean primitive.