Tens Properties

Question 1

5 x 2 Pair

Answer 1

If the prime factorization of a number has a 5x2 pair, that number will have a zero in the units digit. In other words, each 5x2 pair creates one trailing zero

Question 2

Trailing zeros

Answer 2

The number of 5x2 pairs in the prime factorization of a number. Created by powers of 10,
520: 52 x 10 with 1 trailing zero
5,200: 52 x 100 (52 x 10^2) with 2 trailing zeros
5,200,000: 52 x 10^5 with 5 trailing zeros

Question 3

Trailing zero in factorials

Answer 3

Any factorial greater than or equal to 5! will have zero as its units digit (bc of the 5x2 pair)