Vă rog! ! ! ! ! ! urgent!!!!

71/35+(64/21-75/14)-(25/28 + (13/12-31/14))
71/31 + (-97/42) - (25/28 +(25/28+(-95/84))
71/35-97/42 - (25/28-95/84)
71/35-97/42-(-5/21)
71/35-97/42+5/21
=-3/70