Question

15•10+(30-20)•5=
15•10+30-20•5=
(120+320:4)•2=
(120+320):(4•2)=

Answer 1

15*10+(30-20)*5=800
15*10+30-20*5=80
(120+320:4)*2=400
(120+320):(4*2)=55