Answer:
Option D
Step-by-step explanation:
A reporter collects a random sample of 50 runners from all the runners who finished the Cherry Blossom Ten Mile Run in 2009 and constructs a 99% confidence interval for the true mean finish time to be (86.05, 99.38) minutes.
Assuming the reporter performed the calculations correctly, which of the following statements are appropriate interpretations of this confidence interval?
We can expect that 99% of confidence intervals created using the same method the reporter used will contain the true mean run time for runners of this race.
165/3=55 mph
650/55=h
650/(165/3)=h
(650*3)/165=h
3/165=h/650
h/650=3/165
so it is the third option
Substitution is where we first Isolate one of the unknowns, express it in terms of the other unknown, and replace the isolated unknown with the other unknown in another equation. So that each time we only need to deal with one unknown. I think you'll get a better idea here:
First name these 2 equations with 1 and 2.
4x + 5y = 7 (1)
y = 3x + 9 (2)
Since y is already isolated in (2), so we can skip the isolation step and continue to substitute.
Substitute (2) into (1).
4x + 5(3x+9) = 7
Expand.
4x + 15x + 45 = 7
Group.
19x + 45 = 7
Shift +45 to the other side and turn it into -45.
19x = 7 - 45
19x = -38
Shift x19 to the other side, turn it into /19.
X = - 38/19
X = - 2
Now we solved x already, we can just substitute x= - 2 back to equation (2).
y = 3(-2) + 9
y = - 6 + 9
y = 3
So, the answers are
x = - 2
y = 3
Answer:
got what right?
Step-by-step explanation: