The company has to study 199 machines.
In statistics, the standard deviation is a measure of the amount of variation or dispersion of a set of values. A low standard deviation indicates that the values tend to be close to the mean of the set, while a high standard deviation indicates that the values are spread out over a wider range.
It is given that;
Margin of error E = 0.7
Confidence interval 98% = 1-0.98 = 0.02
Standard deviation = 6 hours
Number of MRI machines needed per day n, = [(z alpha/2 * SD)/E]²
Z alpha/2 = 1.645 at alpha = 0.1
Inputting these values into n we have that
[(1.645*6)/0.7]²
= 14.1²
= 198.81 is approximately equal to 199
The company has to study 199 machines.
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Y = x² + 7x - 4
y = -x - 4
x² + 7x - 4 = -x - 4
+ x + x
x² + 8x - 4 = -4
+ 4 + 4
x² + 8x = 0
x(x) + x(8) = 0
x(x + 8) = 0
x = 0 or x + 8 = 0
- 8 - 8
x = -8
y = -x - 4
y = -0 - 4
y = 0 - 4
y = -4
(x, y) = (0, -4)
or
y = -x - 4
y = -(-8) - 4
y = 8 - 4
y = 4
(x, y) = (-8, 4)
The solutions are (0, -4) and (8, -4).
Answer:
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Step-by-step explanation:
Evaluate.
1934917632
this is evaluation
First, use distributive property on the right half.
2 * 5 = 10
2 * 2n = 4n
4n - 9 = 10 + 4n
Add 9 to both sides
4n = 19 + 4n
Subtract 4n from both sides
0 = 19
But thats not true. Therefore, there is no solution.