The total cost of an office dinner was shared equally by k of the n employees who attended the dinner. What was the total cost of the dinner?

(1) Each of the k employees who shared the cost of the dinner paid $19.
(2) If the total cost of the dinner had been shared equally by k + 1 of the n employees who attended the dinner, each of the k + 1 employees would have paid $18.

stmnt1:

Kmembers each paid $19
==> total cost is 19K
but the total cost can not be found as we do not know how many (K) members paid that amount.
NOT SUFF.

stmnt2:

K+1 members paid $18 each
==> total cost is 18(K+1)
but the total cost can not be found as we do not know how many (k+1) members paid that amount.
NOT SUFF.

1&2 together

it is implied that the amount paid by K members, each paying $19, is equilent to that paid by K+1 members, each paying $18

==> 19K = 18(K+1)

==> K=18
==> the toal cost of the dinner is 19K = 18(K+1) = 18*19= $342 (costly dinner, i would never go to that restaurant)

Answer C.

Now in the GMAT way (with out using variables such as x).

the total cost is paid by K members each paying $19
and also given that
the total cost could have been paid by K+1 members if each had payed $18

Means

if we added one person into the payees list, the cost for each person would be REDUCED by $1 (from 19to 18) making the new person to pay $18. this implies that the new person has bared $18 of the total cost and made each of the original list of ppl to pay $1 less. implies, The # of original ppl shud be 18 so that the new person can pay $18 baring $1 from each of the original list of people (original payees).

means the orginal people were 18 and paid $19 each
OR
with an additional person , the total # of people is 19 each paying $18

==> the total cost = 18*19 OR 19*18

TRY solving the GMAT questions in the second way. Most of the word problems can be. It is called "THINK without INK".
Hope it helps.

Regards,
Murali.

Kudos?

"The total cost of an office dinner was shared equally by k of the n employees who attended the dinner" means that there were total of n employees and k employees out of n shared equally the cost of the dinner.
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