3) A= (9/72 + 16/72 - 18/72)·36/7 :(14/18 - 12/19 +3/18) =
=[(9+16-18)/72]·(36/7):[(14-12+3)/18]=
=(7/2)·(1/7):(5/18) = 1/2 :5/18 = (1·18):(2·5) = 18/10=9/5
A= 1+ 4/5 = 1 4/5 = 1,8
4) B=(10+3/4 - 12:(6/5))·(4/9) +13/6 + (13/4):(26/5)=
=(10+3/4 - 12·5:6)·(4/9) +13/6 +(13·5)/(4·26) =
=(10+3/4 - 10)·4/9 +13/6 + 5/8= 3/4 · 4/9 +13/6 + 5/8 =
= 1/3 + 13/6 + 5/8 = 8/24 + 52/24 + 15/24 = 75/24 = 25/8
B = 3+1/8 = 3 1/8 = 3"1/8 = 3.,125