原式=[1/30-(7/4÷7/5+7/4÷7/2)]÷(-11/8)
=[1/30-(7/4*5/7+7/4*2/7)]*(-8/11)
=[1/30-(5/4+2/4)]*(-8/11)
=[1/30-7/4]*(-8/11)
=(2/60-105/60)*(-8/11)
=(-103/60)*(-8/11)
=(-103/15)*(-2/11)
=206/165
原式=[1/30-(7/4÷7/5+7/4÷7/2)]÷(-11/8)
=[1/30-(7/4*5/7+7/4*2/7)]*(-8/11)
=[1/30-(5/4+2/4)]*(-8/11)
=[1/30-7/4]*(-8/11)
=(2/60-105/60)*(-8/11)
=(-103/60)*(-8/11)
=(-103/15)*(-2/11)
=206/165