Here are we considering that the cost of 50 calls in both connections he paid( which would have been free in 1 st situation) and the remaining from Y and Z, after removing 50 each, are paid with X rs.? I didn’t get that X-100=50?
Earlier he would have paid X two times, now he is paying it once. So he is saving X. Also he is paying for 50 calls which he would otherwise have got free. So he should be paying 100 more. Overall effect is a saving of X – 100 (which we are told works out to 50)
CAT-holics 
Here are we considering that the cost of 50 calls in both connections he paid( which would have been free in 1 st situation) and the remaining from Y and Z, after removing 50 each, are paid with X rs.? I didn’t get that X-100=50?
Earlier he would have paid X two times, now he is paying it once. So he is saving X. Also he is paying for 50 calls which he would otherwise have got free. So he should be paying 100 more. Overall effect is a saving of X – 100 (which we are told works out to 50)
regards
J
but in the case when he is using single connection, He is availing 50 calls free, right? why that part is not considered?
like earlier he would have got 100 calls free and now 50, so overall effect is x-50=50 , right?
Yes, I am only looking at the difference between the two scenarios. So 50 EXTRA calls free but one EXTRA entry fee to be paid is all I am comparing.
regards
J
Ok got it now..thanks:)
Sir,
How about taking 100-X=50?
we get X=50, Y=120, Z=140 it satisfy (1) and(2) but fails for (3)
How to distinguish from 100-X/X-100?
Because the cost becomes 50 less and not 50 more.
regards
J