alltimeacheiver wrote:

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:

\(K\)members 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 \(19\)to \(18\)) 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?