16. Сократите дроби.

а) 14/21 = 2/3, 12/30 = 2/5, 24/60 = 2/5, 35/105 = 1/3. б) 55/77 = 5/7, 81/270 = 3/10, 75/450 = 1/6, 135/180 = 3/4. в) 140/210 = 2/3, 105/165 = 2/3, 144/360 = 2/5, 240/560 = 3/7. г) 30/150 = 1/5, 80/200 = 2/5, 21/36 = 7/12, 91/108 = 13/12.