(4分之3加六分之一减3分之1)×12
=3/4x12+1/6x12-1/3x12
=9+2-4
=7
22分之9乘8分之7乘9分之4乘21分之11
=(9/22x4/9)x(7/8x11/21)
=2/11x11/24
=1/12