Well, isn't that a happy little question! When you calculate the factorial of a number, you multiply that number by all the positive integers less than it. The last digit of factorial 99 is 0, because there are lots of factors of 2 and 5 in the multiplication, creating zeros at the end. Just imagine all those zeros as little trees in a beautiful forest of numbers!
Chat with our AI personalities
50
It is 99. 99*99 = 9801
99. Its 99. Wow Did you mean to say the largest odd two digit number?
There are 18 numbers with 2 digits that are divisible by 5. First 2 digit number is 10 → 10 ÷ 5 = 2 → first 2 digit number divisible by 25 is 5 × 2 Last 2 digit number is 99 → 99 ÷ 5 = 19 4/5 → last 2 digit number divisible by 5 is 5 × 19 → There are 19 - 2 + 1 = 18 numbers with 2 digit divisible by 5.
No. When adding the smallest 2 digit number (= 10) to the smallest 2 digit number (again, 10) the result is a 2 digit number (10 + 10 = 20). When adding the largest 2 digit number (= 99) to the largest 2 digit number (again, 99) the result is a 3 digit number (99 + 99 = 198). As you can see, you'll either get a 2 or 3 digit number, but never a 4 digit number.