You can obtain information about the mean population by taking a random sample of it and taking the average of that sample. The Law of big Numbers says that the bigger the sample, the more likely we will be closer to the real mean value. In other words, the margin of error is less likely to be big.
 
        
             
        
        
        
Answer:
110 test
Step-by-step explanation:
Let
x ----> the number  of packet of 10 test
y ----> the total cost
we know that
The number of packet of 10 test purchase multiplied by $11 plus the enrollment fee of $30 must be equal to $151
so
The linear equation that represent this scenario is

we have

substitute

Solve for x
subtract 30 both sides


Divide by 11 both sides

The number of packets purchase was 11
To find out the number of test, multiply the number of packets by 10

 
        
             
        
        
        
The question is incomplete:
Before leaving to visit Mexico, Levant traded 270 American dollars and received 3,000 Mexican pesos. When he returned from Mexico, he had 100 pesos left.
How much will he receive when he exchanges these pesos for dollars?
Answer:
9 dollars
Step-by-step explanation:
To find the amount that Levant will receive when he exchanges these pesos for dollars, you can use a rule of three using the information provided:
270 dollars   →  3,000 Mexican pesos
         x           ←  100 Mexican pesos
x=(270*100)/3,000=9 dollars
According to this, the answer is that he will receive 9 dollars.
 
        
             
        
        
        
Answer:
325.5
Step-by-step explanation:
multiply 62 and 5.25 to get 325.5