You doing virtual school too
We have that
<span> 5x/7=22
multiply by 7 both sides
5x=22*7-------> 5x=154
divide by 5 both sides
x=154/5
x=30.8--------> x=30 4/5
the answer is
x=30 4/5</span>
X-3y=18
X always has a 1 in front of it so
1x-3y=18
-1x -1x You will have to get -3y by its self.
-3y=-1x + 18 when you move 1x over the = it turns into a -1x
/-3 /-3 /-3 divided everything by -3 to get y by its self
Y= 1/3 - 6 and that is you answer
Write it out then put put it as standard notation then multiply 7 with 30 and 5 then get answer and add it up and that would be ur final answer
The 25th percentile corresponds to z ≈ -0.67.
The 90th percentile corresponds to z ≈ 1.28.
So, you can write two equations in μ and σ as here:
.. μ -0.67σ = 10
.. μ +1.28σ = 20
The solution is
.. μ ≈ 13.45
.. σ ≈ 5.11