Answer:
Step-by-step explanation:
The constant increase every hour indicates a linear correlation, which can be represented by an arithmetic sequence.
The nth term formula is a formula for any specific term you wish to find.
The formula is:
a = starting value of the sequence
d = the common difference (i.e. the difference between any two consecutive terms of the sequence)
n = the value corresponding to the position of the desired term in the sequence (i.e. 1 is the first term, 2 is the second, etc.)
Un = the actual vaue of the the term
In this case:
a = 40
d = 10
And so, the nth term formula is:
As long as your indexes are the same (which they are; they are all square roots) and you radicands are the same (which they are; they are all 11), then you can add or subtract. The rules for adding and subtracting radicals are more picky than multiplying or dividing. Just like adding fractions or combining like terms. Since all the square roots are the same we only have to worry about the numbers outside. In fact, it may help to factor out the sqrt 11:
. The numbers subtract to give you -9. Therefore, the simplification is
The answer is: 
The explanation is shown below:
1. Cynthia rounds the number, which is identified as 
, to one decimal place and the result is 6.3.
2. Based on this, we know that could have been between 6.25 and 6.35. Therefore, the error interval for is given by:
Where 
indicates that the value 6.25 is included and 
indicates that the value 6.35 is not included (Because if had been exactly 6.35, Cynthia would round up to 6.4).
