What is the ones digit in the value of the following expression?

1 x 3 x 5 x 7 x 9 x 11 … x 97 x 99

What is the ones digit in the value of the following expression?

1 x 3 x 5 x 7 x 9 x 11 … x 97 x 99

TKPSyoungerbrother

All the numbers in the expression are odd numbers.

Any odd number multiplying 5 will end up to have 5 at the ones digit.

For example, 1 x 5 = 5, 3 x 5 = 15, 7 x 5 = 35 …

Thus, the product of all these odd numbers in the expression is an odd number and is a multiple of 5.

So the ones digit of the above expression is 5.