Discussion

Answer: B

The 4-digit numbers range from 1000 to 9999. The first 4-digit number divisible by 15 is 1005 (since \(1000 \div 15 = 66\) rem 10, so \(15-10=5\) needs to be added). The last 4-digit number divisible by 15 is 9990 (since \(9999 \div 15 = 666\) rem 9, so \(9999-9=9990\)). The numbers form an Arithmetic Progression. The number of terms is \(\frac{\text{Last Term} - \text{First Term}}{\text{Common Difference}} + 1 = \frac{9990 - 1005}{15} + 1 = \frac{8985}{15} + 1 = 599 + 1 = 600\).