Answer:
At least 75% of these commuting times are between 30 and 110 minutes
Step-by-step explanation:
Chebyshev Theorem
The Chebyshev Theorem can also be applied to non-normal distribution. It states that:
At least 75% of the measures are within 2 standard deviations of the mean.
At least 89% of the measures are within 3 standard deviations of the mean.
An in general terms, the percentage of measures within k standard deviations of the mean is given by 
.
In this question:
Mean of 70 minutes, standard deviation of 20 minutes.
Since nothing is known about the distribution, we use Chebyshev's Theorem.
What percentage of these commuting times are between 30 and 110 minutes
30 = 70 - 2*20
110 = 70 + 2*20
THis means that 30 and 110 minutes is within 2 standard deviations of the mean, which means that at least 75% of these commuting times are between 30 and 110 minutes
Answer:
590/1000
Step-by-step explanation:
<h3>
Answer: 161 degrees</h3>
=========================================================
Explanation:
Line AE is a tangent while line AU is a secant. The angle formed by the secant and tangent lines connects with the arcs through this formula
secant tangent angle = (larger arc - smaller arc)/2
More specifically, we can say:
angle EAI = (arc EU - arc IE)/2
42 = ( (7m+5) - (3m-1) )/2
42*2 = (7m+5) - (3m-1)
84 = 7m+5 - 3m+1
84 = 4m+6
4m+6 = 84
4m = 84-6
4m = 78
m = 78/4
m = 39/2
m = 19.5
Use this value of m to compute each arc
- arc IE = 3m-1 = 3*19.5-1 = 57.5 degrees
- arc EU = 7m+5 = 7*19.5+5 = 141.5 degrees
Let's say arc IU is some unknown number x. It must add to the other two arc measures to form 360 degrees, which is a full circle.
(arc IU) + (arc IE) + (arc EU) = 360
x + 57.5 + 141.5 = 360
x + 199 = 360
x = 360-199
x = 161
The measure of minor arc IU is 161 degrees
Answer:
x=9
Step-by-step explanation:
Add similar elements: -5x+3x=-2x
-2x+15=-3
Subtract 15 from both sides
-2x + 15-15=-3-15
Simplify
-2x=-18
Divide both sides by -2
-21/-2 = -18/-2
Simplify
x=9
Adding both equations cancels y:
<span>4x + 8y = 16
</span><span>4x - 8y = 0
-----------------+
8x = 16 => x=2
filling in x=2 in the first equation gives:
4*2 + 8y = 16 => 8y = 8 => y=1
So (2,1) is the (x,y) pair that solves the two equations. Answer C.</span>
