4/5÷(5/6-3/4)-1/15用简便方法怎么算？

4/5÷（5/6-3/4）-1/15
=4/5÷（20/24-18/24）-1/15
=4/5÷2/24-1/15
=4/5×12-1/15
=48×3/15-1/15
=（144-1）/15
=143/15
=9又15分之8

4/5*12-1/15
=48/5-1/15
=143/15