Answer: B.
Step-by-step explanation:
Let's solve your system by elimination.
4x−2y=8;−2x+2y=6
Add these equations to eliminate y:
4x-2y=8
-2x+2y=6
2x=14
Substitute 7 for x in 4x−2y=8:
(4)(7)−2y=8
−2y+28=8 (Simplify both sides of the equation)
−2y+28+−28=8+−28 (Add -28 to both sides)
−2y=−20
−2y/−2=−20/−2 (Divide both sides by -2)
y=10
Answer:
The ratio of the difference of the two means to Sidney's mean absolute deviation = = 1.2195
Step-by-step explanation:
P.S - The exact question is -
Given - The means and mean absolute deviations of Sidney’s and Phil’s grades are shown in the table below.
Sidney’s Grades Phil’s Grades
Mean 82 78
Mean Absolute Deviation 3.28 3.96
To find - Which expression represents the ratio of the difference of the two means to Sidney’s mean absolute deviation?
Proof -
Given that Mean of Sidney Grades = 82
Mean of Phil's Grades = 78
So,
The difference of two means = 82 - 78 = 4
Also,
Given, Mean Absolute Deviation of Sydney = 3.28
Now,
The ratio of the difference of the two means to Sidney's mean absolute deviation = = 1.2195
