There are two parts in the given collection. One contains quarters and other contains dimes.
Let's compare the whole coin collection to the quarters.
One way to represent the ratio is 15 : 7.
The other way is 
<span>A. 3(6)-1/2(6)+1 this is the answer
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15.40 becauwe 6 makes 9to 0 and it makes 3 to 4
The difference between 100 and 75 is 25.
So the following is the answer of the following question in your problem and please do not post to many question in just one posting.
#1 The 98% confidence interval for the mean hours is between 6 and 50.
#2 The smallest margin of error between the two is southern florida with 1.8% margin of error.