Time = Distance / speed
Time = 20 miles / 12mph
Time = 1 and 2/3 hours ( 1 hour and 40 minutes)
Answer:
17 i think
Step-by-step explanation:
Answer:
−2(−9x+5)−4x=2(x−5)−4
Step 1: Simplify both sides of the equation.
−2(−9x+5)−4x=2(x−5)−4
(−2)(−9x)+(−2)(5)+−4x=(2)(x)+(2)(−5)+−4(Distribute)
18x+−10+−4x=2x+−10+−4
(18x+−4x)+(−10)=(2x)+(−10+−4)(Combine Like Terms)
14x+−10=2x+−14
14x−10=2x−14
Step 2: Subtract 2x from both sides.
14x−10−2x=2x−14−2x
12x−10=−14
Step 3: Add 10 to both sides.
12x−10+10=−14+10
12x=−4
Step 4: Divide both sides by 12.
12x
12
=
−4
12
x= -1/3
Step-by-step explanation:
Good luck! Hope this helps! <3
A line is 180 so you subtract 126 with 180 and get 54. Since a Triangle angles all equal 180 together you add 54 and 43 and subtract 180 and the answer is 83
Answer:
--- Standard deviation
Step-by-step explanation:
Given
See attachment for graph
Solving (a): Explain how the standard deviation is calculated.
<u>Start by calculating the mean</u>
To do this, we divide the sum of the products of grade and number of students by the total number of students;
i.e.

So, we have:



Next, calculate the variance using the following formula:

i.e subtract the mean from each dataset; take the squares; add up the squares; then divide the sum by the number of dataset
So, we have:



Lastly, take the square root of the variance to get the standard deviation


--- approximated
<em>Hence, the standard deviation is approximately 11.28</em>
Considering the calculated mean (i.e. 82.76), the standard deviation (i.e. 11.28) is small and this means that the grade of the students are close to the average grade.