(1)325+675÷25×18
=325+675×4×18÷(25×4)
=325+2700×18÷100
=325+486
=811
(2)6.5×0.8-0.8÷0.16
=6.5×0.8-0.8×6.25
=(6.5-6.25)×0.8
=0.25×0.8
=0.2
(3)八分之七×0.75+0.125×四分之三
=7/8×3/4+1/8×3/4
=(7/8+1/8)×3/4
=3/4
(4)六分之一+六分之五÷(六分之五-四分之一)
=1/6+10÷(10-3)
=1/6+10/7
=67/42