Answer:
18/5 = 3.6 (note that 3/2 = 1.5 )
the actual division is 3.387
Step-by-step explanation:
To solve this, we use the z test.
The formula:
z = (x – u) / s
where x is sample value = 20, u is the mean = 15, and s is
the standard deviation = 2.5
z = (20 – 15) / 2.5
z = 2
Since we are looking for values greater than 20, this is
right tailed test. We use the standard distribution tables to find for P.
P = 0.0228
Therefore:
number of students = 100 * 0.0228 = 2.28
<span>2 to 3 students will get greater than 20 measurement</span>
Answer:
No solution
Step-by-step explanation:
To eliminate is to get rid of one of the variables.
You can choose to either add each term in the equations or subtract each term in the equation.
For a variable to be eliminated, there must one pair that have the same constant with it. Each equation already has the same constant with a variable.
Try adding them.
. y - x = 15
<u>+ y - x = 5</u>
2y - 2x = 20 No variables were eliminated.
Try subtracting.
. y - x = 15
<u>- y - x = 5</u>
0y - 0x = 10 All variables were eliminated.
. 0 = 10 This is false.
This system of equations cannot be solved.
Graphically, these two lines would have the same slope and are parallel. The solution to a system is same as the point of intersection. Parallel lines never meet, never intersect, therefore there is no solution.
Answer: x = a*y + 3
Step-by-step explanation:
To make x the subject of the equation, first, we open the bracket
4x - 12/a = y
Then cross multiply:
4x - 12 = a * y ( a*y means the product of the two variables)
Add 12 to both sides of the equation
4x = a*y + 12
Divide both sides by 4 to get the value of x
x = a * y + 12/4
x = a*y + 3
I hope this helps.