sentence1: Find the area of a rectangular field if John walking at the speed of less than 78 m / min took 20 seconds to cross the field diagonally and Harry walking at a speed of 72 m / min took 15 seconds to cross the field along its sides .
sentence2: Find the area of a rectangular field if John walking at the speed of 48 m / min took 20 seconds to cross the field diagonally and Harry walking at a speed of 72 m / min took 15 seconds to cross the field along its sides .