It is 60 meters long and 40 meters wide. Later, the length increased by 20 meters and the width increased by 10 meters. How many square meters did the area increase?

It is 60 meters long and 40 meters wide. Later, the length increased by 20 meters and the width increased by 10 meters. How many square meters did the area increase?

1600 square meters
(60+20)*(40+10)-60*40=1600㎡