Answer:
Step-by-step explanation:
3(a+3)-6=21
<=>3a+9-6=21
<=>3a+3=21
<=>3a=18
<=>a=6
Answer:
the answer is 180 dollars
Step-by-step explanation:
20 is 10% of 200 so just subtract that
Answer:

Step-by-step explanation:
Given: 76,45,64,80,92
Required: Determine the standard deviation
We start by calculating the mean

Where x-> 76,45,64,80,92 and n = 5



Subtract Mean (71.4) from each of the given data

Determine the absolute value of the above result

Square Individual Result

Calculate the mean of the above result to give the variance


Hence, Variance = 255.298
Standard Deviation is calculated by 



Answer:
false
Step-by-step explanation:
just trust me