100.?...........................
To write the problem out as an equation, let 'n' equal your number.
(15 x 1/n) - 3n
16.24 ÷ 1,000 = 0.01624
Good luck! <3
The answer would be: D-100. The reasoning of this is because if you take 3 X 10 to the third power and did the exponent (10 to the third power in this case) and multiplied it you would obviously get 1,000 for an answer. Then would would do 1,000 X 3 to get 3,000.