口算．18-19=17+15=2-25=37+47=1213-113=1112-16=89+411+19=1-16-56=78-38+38=5-712-512=

Question

口算． (1)/(8)-(1)/(9)=	(1)/(7)+(1)/(5)=	2-(2)/(5)=	(3)/(7)+(4)/(7)=
(12)/(13)-(1)/(13)=	(11)/(12)-(1)/(6)=	(8)/(9)+(4)/(11)+(1)/(9)=	1-(1)/(6)-(5)/(6)=
(7)/(8)-(3)/(8)+(3)/(8)=	5-(7)/(12)-(5)/(12)=

Answer 1

(1)/(8)-(1)/(9)=(1)/(72)，	(1)/(7)+(1)/(5)=(12)/(35)，	2-(2)/(5)=1(3)/(5)，	(3)/(7)+(4)/(7)=1，
(12)/(13)-(1)/(13)=(11)/(13)，	(11)/(12)-(1)/(6)=(3)/(4)，	(8)/(9)+(4)/(11)+(1)/(9)=1(4)/(11)，	1-(1)/(6)-(5)/(6)=0，
(7)/(8)-(3)/(8)+(3)/(8)=(7)/(8)，	5-(7)/(12)-(5)/(12)=4．