Since the sample size is less than 30, therefore we use
the t statistic.
Let us define the given variables:
N = sample size = 25
X = average score = 76
s = standard deviation = 12
99% Confidence interval
Degrees of freedom = n – 1 = 24
The formula for confidence interval is given as:
CI = X ± t * s / sqrt N
using the standard distribution table, the t value for DF
= 24 and 99% CI is:
t = 2.492
Therefore calculating the CI using the known values:
CI = 76 ± 2.492 * 12 / sqrt 25
CI = 76 ± 5.98
CI = 70.02, 81.98
Answer: The average score ranges from 70 to 82.
Just plug the corresponding x value on the left of a,b,c, and d into the equation. If you don't understand the equation, it is asking you to multiply x by 3 and then subtract 2.
These are the answers:
-11, -5, 1, 4.
Good luck!
-RxL
Answer:
The solution of the equation are x = - 1 , y = 0 and z = 3
Step-by-step explanation:
Given three linear equation as :
6 x - y + z = - 3 ......A
4 x - 3 z = - 13 ......B
2 y + 5 z = 15 ......C
Solving eq A and C
I.e 2× (6 x - y + z ) = -3 ×2
or, 12 x - 2 y + 2 z = - 6
So, ( 12 x - 2 y + 2 z ) + ( 2 y + 5 z) = - 6 + 15
Or, 12 x + 7 z = 9 ......D
Solving eq B and D
I.e 3 × ( 4 x - 3 z ) = - 13 × 3
or, 12 x - 9 z = - 39
So, ( 12 x + 7 z ) - ( 12 x - 9 z ) = 9 + 39
or, 16 z = 48
∴ z = 
i.e z = 3
put the value of z in eq D
So, 12 x + 7×3 = 9
Or, 12 x = 9 - 21
or, 12 x = - 12
∴ x = - 
I.e x = - 1
Now, Put The value of z in eq C
or, 2 y + 5 z = 15
or, 2 y + 5 × 3 = 15
Or, 2 y = 15 - 15
or, 2 y = 0
∴ y = 0
Hence The solution of the equation are x = - 1 , y = 0 and z = 3 Answer
This is division of 2 complex numbers.
2__ =
3 - i
Multiply both numerator and denominator by conjugate number of the denominator.
2 * 3+ i =
3 - i 3 +i
separate the rational and irrational numbers from
each other
6 + 2i = 3 + 1 i
10 5 5
This is also division of 2 complex numbers into each other.
For this you have to do sin of 30 degrees so if you have a calculator put sin(30)= a/44 and solve for a
