Answer:
y=69
Step-by-step explanation:
first step:when y=26 and x=21
c=y-x
c=26-21
c=5
second step: when y is unknown and x=64
To find y we simply add the value of c to x
y=x+c
y=64+5
y=69
I don’t think there’s a solution
Answer:
x=3 and 9
Step-by-step explanation:
; x-3=0
x=3 (change side change mark)
and
change side change mark.
So, x=9
If u wanna check the answer you can check by substitution x=3 and 9 in equation.
hope it helps you ☺️
Answer:
3.4
Step-by-step explanation:
Standard deviation of a population is defined as:
σ² = ∑(xᵢ − μ)² / n
The standard deviation of a sample is defined as:
s² = ∑(xᵢ − x)² / (n - 1)
It's not clear which one we have, so let's calculate both.
First, we must find the mean.
μ = (5+12+15+10+12+6+8+8) / 8
μ = 9.5
Now we find the squares of the differences:
(5-9.5)² + (12-9.5)² + (15-9.5)² + (10-9.5)² + (12-9.5)² + (6-9.5)² + (8-9.5)² + (8-9.5)²
= 80
Divide by n:
σ² = 80 / 8
σ² = 10
And take the square root:
σ = √10
σ ≈ 3.2
That's not one of the answers, so let's try the standard deviation of a sample instead of a population.
Instead of dividing by n, we'll divide by n-1:
s² = 80 / 7
And take the square root:
s = √(80/7)
s ≈ 3.4
So that must be it.
Equivalent lines for sure
