How many 3-digit numbers are divisible by 7?

✓ Correct Answer: Option B

First: 105 (7×15). Last: 994 (7×142). Count = 142 − 15 + 1 = 128. Actually 7×15=105, 7×142=994. Count = 142−14 = 128. Let me recount: floor(999/7)=142, floor(99/7)=14. 142−14=128. Hmm, 128.