Answer:
15 boys dont finish
Step-by-step explanation:
48+a=63
a=15
Answer: 
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Work Shown:

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Explanation:
The idea is to first get all the y terms to one side. I did this by subtracting 2y from both sides in the third step.
Then factor out y and divide both sides by (8x-2)
Afterward there's the optional steps of simplifying (as shown in the final two steps).
Answer:
Here, Convenience sampling is used by the poll
Explanation:
Convenience sampling also called as opportunity, grab or accidental sampling is a kind of non-likelihood testing that includes the sample being drawn from that piece of the populace that is near hand. This sort of sampling is most valuable for pilot testing.
Convenience sampling is a procedure used to make sample according to straightforward entry, readiness to be a sample's part , accessibility at a given scheduled slot.
So, this method of sampling is biased and don't results in desired outcomes.
What I got was 9/10 or you could make it into a percentage 90% hope this helps