How many positive integers less than 100 are neither multiples of 3 or 5. Pick: A) a)30 B) b)31 C) c)32 D) d)53 E) e)34
To answer this Q we require to know   1) multiples of 5 till 100 = 100/5= 
<gadget id="calculator">100/5</gadget>
<output>20</output>
20   2) Multiples of 3 till 100= 100/3 = 33.33= 33   add the two 20+33= 
<gadget id="calculator">20+33</gadget>
<output>53</output>
53 ; subtract common terms that are multiple of both 5 and 3..   LCM of 5 and 3= 15   Multiples of 15 till 100 = 100/15 = 6   so total multiples of 5 and 3 = 53-6= 
<gadget id="calculator">53-6</gadget>
<output>47</output>
47   ans= 100-47= 
<gadget id="calculator">100-47</gadget>
<output>53</output>
53   d)53
<result>D</result>
How many positive integers less than 100 are neither multiples of 3 or 5.