What is the probability that a two digit number selected at random is a multiple of 3 and not a multiple of 5 ?
Choose the correct choice from the following choices.
A) 1/15  B) 2/15  C) 4/15  D) 7/15  E) None of these
Explanation :   Since every third number starting from 10 will be divisible by 3, so total number of numbers divisible by 3 are   90/3= 
<gadget id="calculator">  90/3</gadget>
<output>30</output>
30   Numbers which are divisible by 3 and 5 both are numbers which are multiple of 15.   For the range 10 to 99, 15 is the first number divisible by 15 and 90 is the last number.   So total number of numbers divisible by 15 are: (90-15)/15 + 1= 5 + 1= 
<gadget id="calculator">5 + 1</gadget>
<output>6</output>
6   Number of numbers which are divisible by 3 are 30 and number of numbers which are divisible by 3 and 5 both are 6. So number of numbers divisible by 3 and not by 5 are: 30-6= 
<gadget id="calculator">30-6</gadget>
<output>24</output>
24   So total probability= 24/90 = 4/15   Answer : 4/15
<result>C</result>
What is the probability that a two digit number selected at random is a multiple of 3 and not a multiple of 5 ?