Question

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

Answer 1

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.