Xiaoxiaojia has a room 5 meters long and 3.9 meters wide, which is paved with 0.5 meters square bricks. How many square bricks should I buy at least?

Xiaoxiaojia has a room 5 meters long and 3.9 meters wide, which is paved with 0.5 meters square bricks. How many square bricks should I buy at least?

5*3.9/(0.5*0.6)