6.3÷[(4又1/7)-0.07÷(1/50)]×(1又2/7)
=6.3÷[(29/7)-(7/100)÷(2/100)]×(9/7)
=6.3÷[(29/7)-(7/2)]×(9/7)
=6.3÷[(58/14)-(49/14)]×(9/7)
=6.3÷(9/14)×(9/7)
=6.3×(14/9)×(9/7)
=6.3×2
=12.6