# Math

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If the average of these four numbers is 21, find the missing number.

12, 18, 28, ?

What is the missing number and why

• Math -

4 * 21 = 84

12 + 18 + 28 = 58

84 - 58 = ?

• Math -

26!

• Math -

Yes!

• Math -

12+18+28+x/4=21 58+x=84 x=84-58=26

• Math -

26

• Math -

26!!!

• Math -

If the average of these four numbers is 21 find the missing number 12,18,28,_,_,_.

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