How many five digit numbers are there such that two left most digits are even…
2023
How many five digit numbers are there such that two left most digits are even and remaining are odd?
Answer: D. 2500 — Key idea: Count valid choices for each digit from left to right. First (leftmost) digit: must be even and cannot be 0 (because the number is five digits) → 4…
- A.
2340
- B.
2400
- C.
2620
- D.
2500
Attempted by 48 students.
Show answer & explanation
Correct answer: D
Key idea: Count valid choices for each digit from left to right.
First (leftmost) digit: must be even and cannot be 0 (because the number is five digits) → 4 choices: 2, 4, 6, 8.
Second digit: even (0 allowed) → 5 choices: 0, 2, 4, 6, 8.
Third, fourth, and fifth digits: each must be odd → 5 choices each: 1, 3, 5, 7, 9.
Total number of such five-digit numbers = 4 × 5 × 5 × 5 × 5 = 4 × 625 = 2500.
Answer: 2500.