In an equilateral triangle all the sides are equal. This means that all the angles add up to 180 degrees.
Divide 180 by 3 and you get 60.
You want an exterior angle so you cut the angle in half ( it is now 30 )
Because the base and the line are parallel (form right angle if drew line connecting them) x is equal to
90-30=60

8 0

2 years ago

The first eight quizzes in this class had average scores of 8,9,9,8,8,9,8,7. This gives a sample mean of 8.25 and a sample stand

alexira [117]

Answer:

Test statistic

$t = \frac{x^{-} -mean}{\frac{S}{\sqrt{n} } }$

t = 1.076

Step-by-step explanation:

Step(i):-

Given Mean of the Population (μ) = 8.0

Mean of the sample (x⁻) = 8.25

Given data

8,9,9,8,8,9,8,7

Given sample size n= 8

Given sample standard deviation(S) = 0.661

Step(ii):-

Null hypothesis : H: (μ) = 8.0

Alternative Hypothesis :H:(μ) > 8.0

Degrees of freedom = n-1 = 8-1=7

Test statistic

$t = \frac{x^{-} -mean}{\frac{S}{\sqrt{n} } }$

$t = \frac{8.25 -8.0}{\frac{0.661}{\sqrt{8} } }$

t = 1.076

Critical value

t₍₇,₀.₀₅₎ = 2.3646

The calculated value t = 1.076 < 2.3646 at 0.05 level of significance

Null hypothesis is accepted

Test the hypothesis that the true mean quiz score is 8.0 against the alternative that it is not greater than 8.0

3 0

2 years ago