Question

The number of natural numbers less than $7,000$ which can be formed by using the digits $0,1,3,7,9$ (repitition of digits allowed) is equal to :

• A. 250
• B. 374
• C. 372
• D. 375

Answer 1

Answer: (B)

374

Answer 2

Number of numbers = $2 \times 5^3$
Required number = $5^3 + 2 \times 5^3 - 1$
= 374