Answer:
a. 1965
b. 8 years
Step-by-step explanation:
For answers to questions like these it can work to consider the smallest possible dataset.
<h3>Dataset</h3>
For our purpose, consider the 9 years/values to be averaged to be ...
1, 2, 3, 4, 5, 6, 7, 8 ,9
<h3>Observations</h3>
a. The center value of the data set is 5. Its number is 5-1=4 more than the first one.
The first centered value is from the year 1961 +4 = 1965.
b. The 4 values at the beginning, and the 4 values at the end do not have a corresponding "average" value. That is, 4+4 = 8 values in the series are lost with respect to the number of average values.
8 years of values are lost.
Answer:
76
Step-by-step explanation:
A full triangle is 180 *always remember
180-153=27
so r is 27
180-77-27=76
or you could do
77+27+x=180
104+x=180
x=180-104
x=76
Lets x to be number of students.
1) If each students get 3 ml, then all students get 3x ml.
There was n ml.
(n-3x) ml leftover
n - 3x = 5
2) If each students get 4 ml.
then all students get 4x ml.
n+21 = 4x
3)
n - 3x = 5
- (n+21 = 4x) -------> -n -21=-4x
n - 3x = 5
<span>-n -21= - 4x
</span>-3x-21=5 - 4x
x=5+21
x=26
Answer : 26 students
Check:
x=26, n-3x = 5, n-3*26=5, n=83
n+21 = 4x
83+21=4*26
104 = 104 true
Answer:
y = -4
Step-by-step explanation:
Solve the following system:
{4 x + 5 y = -12 | (equation 1)
3 y - 2 x = -16 | (equation 2)
Add 1/2 × (equation 1) to equation 2:
{4 x + 5 y = -12 | (equation 1)
0 x+(11 y)/2 = -22 | (equation 2)
Multiply equation 2 by 2/11:
{4 x + 5 y = -12 | (equation 1)
0 x+y = -4 | (equation 2)
Subtract 5 × (equation 2) from equation 1:
{4 x+0 y = 8 | (equation 1)
0 x+y = -4 | (equation 2)
Divide equation 1 by 4:
{x+0 y = 2 | (equation 1)
0 x+y = -4 | (equation 2)
Collect results:
Answer: {x = 2
, y = -4