tính nhanh A=1/5 4/7 1/4 3/7 4/5 1/4= ?

Question

tính nhanh A=1/5 + 4/7 + 1/4 +3/7 + 4/5 + 1/4= ?

dantam45 · Answer

A=1/5+4/7+1/4+3/7+4/5+1/4   A=(1/5+4/5)+(4/7+3/7)+(1/4+1/4)   A=1+1+2/4   A=10/4   A=5/2

giahan44 · Answer

A=1/5+4/7+1/4+3/7+4/5+1/4   =(1/5+4/5)+(4/7+3/7)+(1/4+1/4)   =5/5+7/7+2/4   =1+1+1/2   =2+1/2   =5/2

tính nhanh A=1/5 + 4/7 + 1/4 +3/7 + 4/5 + 1/4= ?