Answer: A. 1.2
Step-by-step explanation:
Given : Sample size : n= 64
Standard deviation: 
The formula to find the standard error of mean is given by :-
Therefore, the standard error of the mean= 1.2
Hence, A is the right option.
Answer:
C) 75 + 50x = 25 + 70x
Step-by-step explanation:
ABC Tech:
$50 an hour. So,for x hours= 50 * x = 50x
Service charge = 75 + 50x
Tech Squad:
$70 an hour. So,for x hours= 70 * x = 70x
Service charge = 25 + 70x
C) 75 + 50x = 25 + 70x
50x - 70x = 25 - 75
-20x = -50
x = -50/-20
x =5/2 = 2
hours
Answer: Im not too good at math but I will try to help and I will say 70 is the answer...?
Im really sorry if I get this wrong
Answer: 40
Step-by-step explanation:
The angles form a straight angle, so y = 180 - 80 - 60 = 40.
Answer:
Step-by-step explanation:
Given the following complex numbers, we are to expressed them in the form of a+bi where a is the real part and b is the imaginary part of the complex number.
1) (2-6i)+(4+2i)
open the parenthesis
= 2-6i+4+2i
collect like terms
= 2+4-6i+2i
= 6-4i
2) (6+5i)(9-2i)
= 6(9)-6(2i)+9(5i)-5i(2i)
= 54-12i+45i-10i²
= 54+33i-10i²
In complex number i² = -1
= 54+33i-10(-1)
= 54+33i+10
= 54+10+33i
= 64+33i
3) For the complex number 2/(3-9i), we will rationalize by multiplying by the conjugate of the denominator i.e 3+9i
= 2/3-9i*3+9i/3+9i
=2(3+9i)/(3-9i)(3+9i)
= 6+18i/9-27i+27i-81i²
= 6+18i/9-81(-1)
= 6+18i/9+81
= 6+18i/90
= 6/90 + 18i/90
= 1/15+1/5 i
4) For (3 − 5i)(7 − 2i)
open the parenthesis
= 3(7)-3(2i)-7(5i)-5i(-2i)
= 21-6i-35i+10i²
= 21-6i-35i+10(-1)
= 21-41i-10
= 11-41i
