How many positive integers less than 100 are there such that they are multiples of 13 or multiples of 12 but not both?
Choose the correct choice from the following answers: A) 15 B) 16 C) 17 D) 18 E) 19
for 13: 13...91=13*7 = 7   for 12: 12...96=12*8 =8   but there is no integer 13*12. so   N=(7)+(8)= 
<gadget id="calculator">(7)+(8)</gadget>
<output>15</output>
15   15
<result>A</result>
How many positive integers less than 100 are there such that they are multiples of 13 or multiples of 12 but not both?