None of these because they all are 0
The equation which can be used to find the number of quarters and nickels is; n + q = 84, 0.05n + 0.25q = 17.80.
<h3>Quarters and nickels</h3>
- Total coins = 84
- Total value = $17.80
let
- Number of quarters = q
- Number of nickels = n
n + q = 84
0.05n + 0.25q = 17.80
From equation (1)
n = 84 - q
Substitute into (2)
0.05n + 0.25q = 17.80
0.05(84 - q) + 0.25q = 17.80
4.2 - 0.05q + 0.25q = 17.80
- 0.05q + 0.25q = 17.80 - 4.2
0.20q = 13.60
q = 13.60 / 0.20
q = 68
Substitute q = 68 into
n + q = 84
n + 68 = 84
n = 84 - 68
n = 16
Therefore, the number of quarters and nickels are 68 and 16 respectively.
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Answer:
Answer is D.
Step-by-step explanation:
Which is not true?
So, lets assess the answers given to the question.
A. It is the equation of a horizontal line.
Yes, it is. Since there is only one y - value which is y = -4, we can confirm this is the y intercept, so therefore the x value is zero. But it's not the answer we're looking for.
B. It's slope is zero, yes the slope is zero. It only lists the y-intercept which confirms that the slope is 0.
C. Yes, I mean i can't really explain how. Just use desmos calculator, the graph is exactly perpendicular.
D. The line actually does cross the x-axis, -4 is the y intercept and the x value is 0, and zero is still a point. So D is the one which isn't correct making it the correct answer.
Answer: 
Step-by-step explanation:
Given
Sample of 12 measurements has a mean of 16.5 and
a sample of 15 measurements has a mean of 18.6
Take
be the mean and no of measurements
and
be the mean and no of measurements in second case

Similarly,

Mean of 27 measurements

Answer:
(C)
Step-by-step explanation:
In order to find whether the given side lengths form a right triangle or not, we must show that it satisfies the Pythagoras theorem.
A.
, 10 and 116
According to Pythagoras theorem,
⇒
⇒
which does not satisfy the condition, therefore these side lengths do not form a right triangle.
B. 3,6 and 8
According to Pythagoras theorem,
⇒
⇒
⇒
which does not satisfy the condition, therefore these side lengths do not form a right triangle.
C. 30, 40 and 50
According to Pythagoras theorem,
⇒
⇒
⇒
which satisfies the condition, therefore theses side lengths form right triangle.