Correct Answer - Option 4 : 3013

**Calculation:**

LCM of 18, 21 and 24 is 504

Let the number be 504k

According to the question

⇒ 504k – [(18 – 7) + (21 – 10) + (24 – 13)]/3

⇒ 504k – (33/3)

⇒ 504k – 11

Put the value of k so that it should be divisible by 23

Put k = 6

⇒ 504 × 6 – 11

⇒ 3024 – 11

⇒ 3013

**∴ The number is 3013**