<h2>
Answer with explanation:</h2>
Let 
be the population mean.
By observing the given information, we have :-
Since the alternative hypotheses is left tailed so the test is a right-tailed test.
We assume that the time spend by students per day is normally distributed.
Given : Sample size : n=121 , since n>30 so we use z-test.
Sample mean : 
Standard deviation : 
Test statistic for population mean :-
Critical value (one-tailed) corresponds to the given significance level :-
Since the observed value of z (-7.79) is less than the critical value (1.2816) , so we do not reject the null hypothesis.
Hence, we conclude that we have enough evidence to accept that the college students spend an average of 4 hours or less studying per day.
Answer:
A
Step-by-step explanation:
∆ABC is similar to ∆DEF if and only if the ratio of their corresponding side lengths are the same.
Let's find out:
DE/AB = 10/5 = 2
EF/BC = 8/4 = 2
FD/CA = 12/6 = 2
The ratio of their corresponding side lengths are equal, therefore, ∆ABC is similar to ∆DEF based on the SSS Similarity Theorem.
Answer:
the width is 360 ft
Step-by-step explanation:
The computation of the width of the flag is shown below:
Let us assume the width be x
So the length would be x + 340
And, the perimeter is 2,120 ft
So the formula is
Perimeter = 2(length + width)
2,120 = 2(x + 340 + x)
2,120 = 2x + 680 + 2x
2,120 = 4x + 680
4x = 2,120 - 680
x = 360
hence, the width is 360 ft
The reflection of a point over the x axis is given by the equation (x, y) ⇒ (x, -y).
If the point (-8,2) is reflected over the y-axis, the new point would be (8, 2)
<h3>What is a
transformation?</h3>
Transformation is the movement of a point from its initial location to a new location. Types of transformation are <em>reflection, translation, rotation and dilation.</em>
The reflection of a point over the x axis is given by the equation (x, y) ⇒ (x, -y).
If the point (-8,2) is reflected over the y-axis, the new point would be (8, 2)
Find out more on transformation at: brainly.com/question/4289712
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Answer:
C.
Step-by-step explanation:
WE need to convert the given equations into the standard form
(x - a)^2 + (y - b)^2 = r^2 where r = the radius.
x^2 + y^2 + 12x - 20y+ 132 = 0
(x + 6)^2 - 36 + (y - 10)^2 - 100 = -132
(x + 6)^2 + (y - 10)^2 = -132 + 36 + 100 = 4
giving a radius of 2
x^2 + y^2 + 12x - 20y + 55 = 0
will give a right hand side of -55 + 36 + 100 = 81 giving radius 9.
x^2 + y^2 - 12x+ 20y + 127 = 0
- gives right hand side of -127 + 36 + 100 = 9 giving a radius of 3.
