{360-【(6-0.5)×25-30×2】}÷(6-0.5)
={360-【137.5-60】}÷5.5
={360-77.5}÷5.5
=282.5÷5.5
=565/11
=51又4/11分
再经过51又4/11分,时针与分针第一次重合