there are 600 seats in the auditoium this is less than the number seats in gymnasum how many seats are in the gymnasium?

(600 + x) seats ... let x be the number seat less than the auditorium in relation to the gymnasium

For example. There are 600 seats in the auditorium. This is 112 less than the number of seats in gymnasium

600 is 112 less, therefore 712 seats in the gymnasium