Question

150:{9x3-[3 416:7+(311-31):8-103]:10}-2x5

Answer 1

150:[27-(488+280:8-103):10]-10
=150:[27-(488+35-103):10]-10
=150:[27-(523-103):10]-10
=150:(27-420:10-10)
=150:(27-42-10)
=150:(27-32)
=150:5
=30