An odd number. (3 x 5 = 15, etc)
Chat with our AI personalities
My conjecture (an opinion based on incomplete information) is that the product of two odd numbers is 22. There is no requirement for a conjecture to be true.
The last digit in the product of the first 20 odd natural numbers can be determined by looking at the pattern of the units digit in the multiplication of consecutive odd numbers. The units digit of the product of consecutive odd numbers alternates between 1 and 5. Since there are 10 odd numbers between 1 and 19, and 20 is also an odd number, the last digit in the product of the first 20 odd natural numbers is 5.
Not enough information.
3, 5, 7
It will alway be even, because it will always be the product of an odd and an even number, which is always even.