420:6+(700-640)*5
= 420:6 + (60)*5= 70 + 300= 370
700-(810-390):7+6*60
= 700 - (420):7 + 6*60= 700 - 60 + 360= 700 - 60 + 360= 640 + 360= 1000
420:6+(700-640)*5
= 420:6 + (60)*5
= 70 + 300
= 370
700-(810-390):7+6*60
= 700 - (420):7 + 6*60
= 700 - 60 + 360
= 700 - 60 + 360
= 640 + 360
= 1000