They should charge $15.25 to make a 22% profit, because 12.50*1.22= 15.25
1. Factor the expression 
2. Since 
is placed in the denominator of the given expression, then 
3. Now the expression can be simplified:
Answer:
6 to the power of 2.
Step-by-step explanation:
Recall that whenever you divide exponents with the same base, you subtract the powers, but the base will still be the same. Therefore, 6 to the power of 12 divided by 6 to the power of 10 is 6 to the power of 2. Subtract the powers (exponents) or 12 minus 10, and you get 2. Since the base doesn't change, it is still 6. The solution to this expression is 6 to the power of 2. Hope this helps!
The phrasing "nine times out of ten" means 9/10 = 0.90 = 90% is the confidence level. We're confident 90% of the time that the confidence interval captures the population parameter we're after (in this case mu = population mean)
The portion "have an average score within 5% of 75%" means that 75% = 0.75 is the center of the confidence interval, and it goes as low as 0.75 - 0.05 = 0.70 and as high as 0.75 + 0.05 = 0.80
This confidence interval is from 70% to 80%, meaning that nine times out of ten, we're confident that the average score is between 70% and 80%
We write the confidence interval as (0.70, 0.80). It's common to use the notation (L, U) to indicate the lower (L) and upper (U) boundaries. You might see the notation in the form L < mu < U. If so, then it would be 0.70 < mu < 0.80; either way they mean the same thing.
The margin of error is 0.05 as its the 5% radius of the interval. It tells us how far the most distant score is from the center (75%)
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In summary, we have these answers
- confidence level = 90%
- margin of error = 5% = 0.05
- confidence interval = (0.70, 0.80)
- interpretation = We're 90% confident that the average exam score is between 0.70 and 0.80
