1/2×11/20+1/2÷20/49簡便運算

1/2×11/20+1/2÷20/49簡便運算

1/2×11/20+1/2÷20/49
=1/2×11/20+1/2×49/20
=1/2×(11/20+49/20)
=1/2×60/20
=1/2×3
=3/2