六年级奥数(10.5
(10.5-10.5/4分之5)*(9/7+0.5)=?
[10.5-10.5/(5/4)]*(9/7+0.5) =10.5(1-4/5)*(9/7+1/2) =10.5*1/5*(25/14) =2.1*25/14 =0.3*7*25/(2*7) =0.3*12.5 =3.75.