Verified answer

Пошаговое объяснение:

а)

(3/5)²•1 2/3+12 2/9=

=9/25•5/3+12 2/9=3/5+12 2/9=

=27/45+12 10/45=12 37/45

б)

13 4/5•1 7/23-(3/4)²=

=69/5•30/23-9/16=18-9/16=

= 17 16/16-9/16=17 7/16

в)

(11 1/4-8 4/5)•(3/7)²=

=(11 5/20-8 16/20)•9/49=

=(10 25/20-8 16/20)•9/49=

2 9/20•9/49=49/20•9/49=9/20