All possible two factor product are formed from the numbers 1,2....100 .the number of factors out of the total obtained from the multiples of 3 .
Two Factor products which are Multiples of 3=(total two factor products)-(two factor products of non multiples of 3)
- Total two factor products=100c2 (any two numbers selected from 100)
- Two factor products of non multiples of 3=67c2 (there are 33 multiples of 3 below 100)
- Final answer=100c2 - 67c2=2739