Question

On Sasha's desk there are c green notebooks. The number of red notebooks on her desk is 6 less than number of green notebooks. How many notebooks are there on Sasha's desk if all of them are either green or red?

Answer 1

Sasha's desk has $c$ green notebooks.

The number of red notebooks on her desk is $c-6$.

Sasha's desk has either green or red notebooks.

The total number of notebooks on Sasha's notebook is $c+c-6=2c-6$.