n(3)⇒ multiple of 3 102,105,108,....,699 Tn=699=102+(n−1)(3) n=200 n(3)=200 ∵n(4)⇒ multiple of 4 100,104,108,....,700 Tn=700=100+(n−1)(4) n=151 n(4)=151 n(3∩4)⇒ multiple of 3&4 both 108,120,132,......,696 Tn=696=108+(n−1)(12) n=50 n(3∩4)=50 n(3∪4)=n(3)+n(4)−n(3∩4) =200+151−50 =301 n(3∪4)= Total −n(3∪4)= neither a multiple of 3 nor a multiple of 4 =601−301=300