（720-t×6）:9＝60 720-t×6＝............... 720-t×6＝............... 720－t＝................

Question

（720-t×6）:9＝60
720-t×6＝...............
720-t×6＝...............
720－t＝.............
720-t＝..........
t＝...........
t＝...........???

Answer 1

(720-t×6):9＝60
720-6t=60*9
720-6t=540
6t=720-540
6t=180
t=180:6
t=30

Answer 2

60•9
540
540:6
90
720-90
630