解:原式=(150-1)×2/75
=150×2/75-1×2/75
=4-2/75
=3又73/75
149×75分之2
=(150-1)×2/75
=150×2/75-1×2/75
=2×2-2/75
=4-2/75
=3又75分之73
149×2/75
=(150-1)×2/75
=150×2/75-1×2/75
=4-2/75
=4-0.02667
=3.9733
149=150-1,
149ⅹ2/75=(150-1)x2/75=150x2/75-1x2/75
=4-2/75=3又73/75