Answer: 70-27x = 50-20x
Step-by-step explanation: First you do 7 x 10 which equals 70 then 7 x -3x equals -27x. Next you do 5 x 10 which is 50 next you do 5 x -4x equals -20x. So your answer is 70-27x = 50-20x
 
        
             
        
        
        
Answer:
8x15x12=1440
Step-by-step explanation:
 
        
             
        
        
        
The area of a triangle is area=1/2•base•height or a= b•h / 2
        
             
        
        
        
Answer:
The standard error of the mean is 0.02
Step-by-step explanation:
Here, we want to calculate the standard error of the mean.
Mathematically;
standard error of mean = SD/ √n
where SD is the standard deviation and n is the number of samples
From the question, SD = 0.22 and n = 121
Inserting this into the equation
Standard error of the mean = 0.22/√121
= 0.22/11 = 0.02