The digit in the units place of the product

The digit in the units place of the product 81×82×83×84×....×99 is

  1. 0
  2. 4
  3. 6
  4. 8

Answer

The product will have the factor of 90, whose units digit is 0. So, units digit in the product is the units digit in 1×2×3×4×...×0×...×9, which will be 0.

So, the units digit is 0.

The correct option is A.