В) 11/13*11/15 + 11/13*2/15 = 11/13• (11/15+ 2/15)= 11/13• 15/15= 11/13• 1/1= 11/13.
г) 12/19*23/15-12/19*4/15 = 12/19• (23/15- 4/15)= 12/19• 19/15= 12/1• 1/15= 12/15= 4/5.
д) 22/21*5/14+20/21*5/14 = 5/14• (22/21+ 20/21)= 5/14• 42/21= 5/14• 2/1= 5/7• 1/1= 5/7.
е) 47/11*1/2-25/11 * 1/2 = 1/2• (47/11- 25/11)= 1/2• 22/11= 1/2• 2/1= 1/1• 1/1= 1.