Find the value of x given a set of numbers is 12, 56, 3, 9, 18, 21, x, 45 and the average is 32.

Question

tkhunny · Answer

How does one calculate an average of 8 values?

anonymous · Answer

by adding then dividing

tkhunny · Answer

What's stopping you from doing that with your 8 values?

anonymous · Answer

not knowing what one value is

tkhunny · Answer

Fair enough.  Just ignore that for now and proceed, anyway.  See if anything useful happens.  You already know what the average is.  Maybe that will help.

anonymous · Answer

okay so i know the avergge is 32 but how is that any help?

tkhunny · Answer

You're not going to do it, are you...

$\dfrac{12+56+3+9+18+21+x+45}{8} = 32$

Are you SURE that's not helpful?

dwelsher · Answer

(12+56+3+9+18+21+x+45)/8=32
164+x=256
x=256-164
x=92

anonymous · Answer

No, I am going to do it I'm just really confused in this. After I added it I get $$164+x \div8=32$$

tkhunny · Answer

Add the parentheses around (164 + x) then multiply everything by 8.  A little faith got us there.  :-)

anonymous · Answer

@dwelsher how did you get 256 on the second line?

tkhunny · Answer

Really?  What's 8 * 32?  You MUST pay better attention.