made easy 2018

Question

The number of positive number which divides either 2700 or 9000 are _________?

 i am getting 20

Comments

@Lakshman Patel RJIT

it is symmetric diiff formula

$n(A\Delta B)=n(A)+n(B)-2n(A\cap B)$

---

@Lakshman Patel RJIT, Draw the Venn diagram you will get it :)
@Shubhgupta @Gate Fever I am also confused in this "either or" thing.
@Mk Utkarsh please check this once. 

---

Case $(1):$Either $A$ $(or)$ $B$  but not both

 Case $(2):$Either $A$ $(or)$ $B$  $(or)$ both

                                  $(OR)$