kira has scored 73, 60, and 86 on her previous three test. what score does she need on her next test so that her average (mean) is 72?

Question

kira has scored 73, 60, and 86 on her previous three test. what score does she need on her next test so that her average  (mean) is 72?

thesmartone · Answer

$\sf\Large average = \frac{sum~of~tests}{total~number~of~tests}$

now we know what the average is and how many tests there are. We don't know the sum of the tests because we only know the scores of 3 of the tests of the 4 tests. Are you following what I'm saying?

thesmartone · Answer

and btw, welcome to OpenStudy! :D

aneles · Answer

Thank you! :)

thesmartone · Answer

Anytime!

And so how many tests are there in total? And what is the final average/mean?

And what are the three test scores that we know?

I can help guide you through the question :)

thesmartone · Answer

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