What percent of the prime numbers less than 100 have a units digit of 3?

28% is the percent of prime numbers less than 100 that have a units digit of 3.

A prime number is a number above 1 that is only divisible by 1 and itself.
There are 25 prime numbers that are below 100.

These numbers are:
  2,   3,   5,   7, 11, 13, 17, 19, 23, 29,
31, 37, 41, 43, 47, 53, 59, 61, 67, 71,
73, 79, 83, 89, 97

There are 7 numbers that have a units digit of 3.
3, 13, 23, 43, 53, 73, 83

The percentage of prime numbers less than 100 that have units digits of 3 is: 28%

7 / 25 = 0.28 * 100% =  28%