How many numbers between 100 and 900 begin or end with 3?
Choose the correct choice from the following answers.
A) 80
B) 100
C) 150
D) 170
E) 190
How many numbers between 100 and 900 begin or end with 3?   Just think that those numbers are:   i) The ones ending in 3: 103, 113, 123, ... , 893 --&gt; 80 numbers   ii) The ones beginning in 3: 300, 301, 302, 303, ... , 393, ... , 399 --&gt; 100 numbers   BUT 10 out of the first 80 numbers are repeated in the second set.   THEREFORE, the solution is 170 numbers.   Answer: 170
<result>D</result>
How many numbers between 100 and 900 begin or end with 3?