Sum divided by count. Add up all the numbers and divide it by how many numbers it is.
        
             
        
        
        
By solving the equation 
1/2 +x =4/7
x = 4/7 -1/2
x= 1/14
        
             
        
        
        
1215 dollars is the right answer. Plz give brainliest!
        
             
        
        
        
Answer:
 c) t-test of population mean 
Explanation:
The t-test statistic is used in hypothesis testing. Here we would use a one sample t test to test our hypothesis. The one sample t test measures the statistical difference between the hypothesized mean and the sample mean. In a one sample t test or single sample t test, a test variable is measured against a test value. 
Example we compare our test variable to the hypothesized mean value $75 above.
The t test is used instead of z score when standard deviation is unknown.
Using the t test, we either accept or reject the null hypothesis given alternative hypothesis.
 
        
             
        
        
        
Answer:
all numbers natural,integer,rational,real algebra comes under real numbers 
except the equations with alphabets