**the average of 3 numbers is 12. if one of the numbers is 8 what are the sum of the other 2 numbers i need help asap**

**8 + X + Y = 36**

**X + Y = 28**

**28**!

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Let the variables X & Y represent the 2 missing numbers.

So, (8 + X + Y)/3 = 12

multiply both sides of the equation by 3 to get **8 + X + Y = 36**

subtract 8 from both sides of the equation to get **X + Y = 28**

So, the sum of the 2 missing numbers is **28**!

To check 8 + 28 = 36 and 36/3 = 12

Good luck!

Steve

Since an average is a sum of numbers divided by the quantity of numbers, I would suggest working this backwards.

Average = (sum of the numbers)/quantity

So, in this case, we know that the quantity of numbers (how many there are) is 3, and we know that the average is 12.

12 = sum/3

To solve this equation, we can multiply both sides by 3.

12 (*3) = sum/3 (*3) which leaves us with...

36 = sum of the three numbers

But we know that one of the numbers is 8, so 36 - 8 = 28. The sum of the other 2 numbers is 28.

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