7+(x-9/24)times40=480

what is x

7+(x-9/24)(40) = 480

40(x - 9/24) = 473
40x - 15 = 473
40x = 488
x = 61/5 or 12.2

check:
LS = 7 + (61/5 - 9/24)(40)
= 7 + (473/40)(40)
= 7 + 473
= 480 = RS

my answer is correct according to the way you typed the problem.