If a class of 6 students has an average of 72 before a seventh joins the class, what must the seventh student's grade be in order to raise the class average to 76?
a]76
b]80
c]88
d]92
e]100
Show your work and explain please!!

Question

If a class of 6 students has an average of 72 before a seventh joins the class, what must the seventh student's grade be in order to raise the class average to 76? 
a]76
b]80
c]88
d]92
e]100
Show your work and explain please!!

terenzreignz · Answer

First, it would be good to find how the original 6 students add up.  If their average is 72, what does that tell you about the sum of all their marks?

anonymous · Answer

@gumstopper Find the sum from average!

anonymous · Answer

The sum of the average is 432

terenzreignz · Answer

That's right.  Now, when you add another student, whose mark, we'll denote with x for now, what would be the average of the seven?

anonymous · Answer

532

anonymous · Answer

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