2015 · Q5
The digit in the units place of the product 81 × 82 × 83 × 84 × × 99 is
Elementary MathematicsNumber System
- A0
- B4
- C6
- D8
Explanation
The product 81×82×…×99 contains the factor 90 = 9×10, so the whole product is a multiple of 10 and its units digit is 0 (option A).