Answer:
   9 hours
Step-by-step explanation:
"At the same rate" means time and wages are proportional.
   time/wages = t/$108 = (13 h)/$156
   t = 108(13 h)/156 . . . . . . . . . . . . . . . units of dollars cancel
   t = 9 h
Chang would have to work 9 hours to make $108.
 
        
             
        
        
        
Answer:
2
Step-by-step explanation:
1,3,4 are arithmetic sequences
2 is a geometric sequence
 
        
                    
             
        
        
        
line given slope = x coefficient = 1/3
Perpendicular slopes must be opposite reciprocals of each other:  m1 * m2 = –1
line slope (m) = -3
line equation formula = y = mx + b
y = -3x + b
from the point given 
x = 3
y= 3
3 = -9 + b
b = 12
y = -3x + 12
 
        
             
        
        
        
m∠A = 40
Step-by-step explanation:
Given AB =AC and  m∠B = 70
Since AB =AC , Triangle ABC is an isosceles Triangle and the corresponding angles B and C are equal.
So m∠B = m∠C = 70
The sum of the 3 Angles of a triangle is 180°. 
=> m∠A  + m∠B + m∠C = 180
=> 140 + m∠C = 180
=> m∠C = 40
Hence the answer is  m∠C = 40
 
        
             
        
        
        
Answer:
A sample of 1068 is needed.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of  , and a confidence level of
, and a confidence level of  , we have the following confidence interval of proportions.
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of  .
.
The margin of error is:

95% confidence level
So  , z is the value of Z that has a pvalue of
, z is the value of Z that has a pvalue of  , so
, so  .
. 
At 95% confidence, how large a sample should be taken to obtain a margin of error of 0.03 for the estimation of a population proportion?
We need a sample of n.
n is found when M = 0.03.
We have no prior estimate of  , so we use the worst case scenario, which is
, so we use the worst case scenario, which is 
Then






Rounding up
A sample of 1068 is needed.