You probably haven't learnt this but the general equations for circle with centre at the origin is x^2+y^2=R^2 where R is the radius of the circle so R^2=(1737+185)^2.I am lazy to press my calculator so type it in yourself.
Answer:
You could just replace all the given possible values of k in the inequality and see which ones are solutions, but let's solve this in a more interesting way:
First, remember how the absolute value works:
IxI = x if x ≥ 0
IxI = -x if x ≤ 0
Then if we have something like:
IxI < B
We can rewrite this as
-B < x < B
Now let's answer the question, here we have the inequality:
I-k -2I < 18
Then we can rewrite this as:
-18 < (-k - 2) < 18
Now let's isolate k:
first, we can add 2 in the 3 parts of the inequality:
-18 + 2 < -k - 2 + 2 < 18 + 2
-16 < -k < 20
Now we can multiply all sides by -1, remember that this also changes the direction of the signs, then:
-1*-16 > -1*-k > -1*20
16 > k > -20
Then k can be any value between these two limits.
So the correct options (from the given ones) are:
k = -16
k = -8
k = 0
Variance is the standard deviation squared but we're not going to use that now. Let's first calculate the mean:
mean = (17+13+13+22+11+20)/6 = 16.
Now for each value, let's see how far it is from this mean. We'll square these distances and average them. That's our variance.
17 distance 1 squared = 1
13 distance 3 squared = 9
13 distance 3 squared = 9
22 distance 6 squared = 36
11 distance 5 squared = 25
20 distance 4 squared = 16
Now average these outcomes:
variance = (1+9+9+36+25+16)/6 = 16.
So the variance by coincidence is the same as the mean.
Answer C is your answer.
1.06, 1.16, 1.6, 1.62, 1.66
