X - the number of pencils
y - the number of pens
She has twice as many pencils as she has pens.

Tom borrows a pen, so she has y-1 pens. Now she has ten less pens than pencils.

Set 2y and y+9 equal to each other:
She has 9 pens.
Look at deonomators
assuming that the deonomenators are 5x+15y and 2x+6y
find their LCM
factor
5x+15y=5(x+3y)
2x+6y=2(x+3y)
LCM=10(x+3y)=10x+30y
multiply 2/(5x+15y) by 2/2=4/(10x+30y)
multiply 1/(2x+6y) by 5/5=5/(10x+30y)
if we add them
9/(10x+30y)
<h3>
Answer: Sample B as it has the smaller sample (choice #4)</h3>
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Explanation:
Recall that the margin of error (MOE) is defined as
MOE = z*s/sqrt(n)
The sample size n is located in the denominator, meaning that as n gets bigger, the MOE gets smaller. The same happens in reverse: as n gets smaller, the MOE gets bigger.
Put another way, a small sample size means we have more error because small samples mean they are less representative of the population at large. The bigger a sample is, the better estimate we will have of the parameter.
We are told that "sample A had a larger sample size" indicating that sample A has a more narrow confidence interval.
Therefore, sample B would have a wider confidence interval.
This is true regardless of what the confidence level is set at.
Answer: 11, 3, and 17
so C E and F
Step-by-step explanation: