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.
Answer:
4 horses and 8 ducks.
Step-by-step explanation:
Let the number of ducks be d and the number of horses be h.
d + h = 12
Now ducks have 2 feet and horses have 4 so:
2d + 4h = 32
Multiply the first equation by 2
2d + 2h = 24
Subtract this equation from the second equation:
4h - 2h = 32 - 24
2h = 8
h = 4.
So there were 4 horses and 12 - 4 = 8 ducks.
72ft
By adding the sides together you get an area of 72ft
Y-8 I’m pretty sure I hope it’s correct!
