Answer: The mean is 27.
Step-by-step explanation: You add up all of the numbers and divide the sum by the amount of numbers you have.
To find out whether or not the equation x^2 - 4x + y^2 = -3 intersects the x-axis, we must set y = 0 in the equation (because at every point on the x-axis, y = 0).
x^2 - 4x + 0 = -3
We then want to solve for x. We can do this by factoring.
x^2 - 4x + 3 = 0
By factoring...
(x - 3)(x - 1)
We can set each of these equations = 0 to solve where the function crosses the x-axis.
x - 3 = 0
x = 3
x - 1 = 0
x = 1
So we know at x = 1 and x = 3, the function x^2 - 4x + y^2 = -3 intersects the x-axis.
Answer:
187
Step-by-step explanation:
A number m is such that when it is divided by 30, 36 and 45 the remainder is always 7.
We should first find the LCM of 30, 36 and 45
We get that the LCM of the three numbers is 280 (working attached).
So now;
= 6
= 5
= 4
But we need a number that leaves a remainder of 7 so we add 7 to 180 to get; 180 + 7 = 187.
Answer:
The score of a person who did better than 85% of all the test-takers was of 624.44.
Step-by-step explanation:
Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula.
In a set with mean and standard deviation , the z-score of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
One year, the average score on the Math SAT was 500 and the standard deviation was 120.
This means that
What was the score of a person who did better than 85% of all the test-takers?
The 85th percentile, which is X when Z has a p-value of 0.85, so X when Z = 1.037.
The score of a person who did better than 85% of all the test-takers was of 624.44.
6(2x+4)=12
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Multiply 6 with numbers in the parenthesis
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12x +24=12
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Subtract 24 to both sides
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12x = 12
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Divide 12 with both sides
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Answer x=1