Explain how to answer please. How would you figure this out?

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1 Answer
Feb 12, 2018

The missing sum is 91

87+86+93+79=345

91+85+87+82 = 345

Explanation:

There are 16 shapes shown in the square.

If each shape represents a number, then they can be added.

There is only one answer for the sum of all the shapes.

The sum of each column has been given so the total for all 16 shapes can therefore be calculated.

87+86+93+79=345

If the sum of all the rows is added, the total has to be the same.

Let the sum of the first row be x

x +85+87+82 must therefore also be equal to 345

x+254 =345

x =345 -254

x=91

It is not necessary to work with the individual values, the sum of each row and column is enough.