Of all the houses on Kermit Lane, 20 have front porches, 20 have front yards, and 40 have back yards. How many houses are on Kermit Lane?
(1) No house on Kermit Lane is without a back yard.
(2) Each house on Kermit Lane that has a front porch does not have a front yard.
How do I know this is an overlapping set of 3 sets? ok, I went straight to statement 1 and I thought t hen the answer would be 40.
same with Statement 2, I thought the ans is d
Ans is A
thanks,