：设一台的进价为m元,另一台的进价为n元．由题意,得m(1+10%)=n(1－10％) …… ①,解之,得m=0.9/1.1n调价后两台售价的和/两台进价的和=(1.1m+0.9n)/(m+n)……②,将m=0.9/1.1n代入②式,得(1.1*0.9/1.1n+0.9n)/(0.9/1.1...