How many positive three-digit integers are divisible by both 3 and 5?	Answers: A) 50 B) 60 C) 65 D) 70 E) 80
A number to be divisible by both 3 and 5 should be divisible by the least common multiple of 3 and 5 so by 15.   Multiples of 15 between 100 and 999, inclusive is   (last-first)/multiple+1=(990-105)/15+1=59+1= 
<gadget id="calculator">59+1</gadget>
<output>60</output>
60   Answer: 60.
<result>B</result>
How many positive three-digit integers are divisible by both 3 and 5?