Bunuel
Brian is selling souvenirs outside of a Detroit Tigers baseball game. He is selling two different items: T-shirts (T) are selling for $22 each and Baseball caps (C) are selling for $19 each. How many T-shirts did Brian sell?
(1) Brian sold a total of 8 souvenirs.
(2) The total value of the souvenirs that Brian sold was $161.
Kudos for a correct solution. VERITAS PREP TUTOR OFFICIAL SOLUTION:This question points convincingly toward answer choice C. If you convert the two statements to equations you get T + C = 8 and 22 T + 19 C = $161. With these two equations together it is possible to solve for the answer.
Yet before you choose C, take a closer look at statement 2. This is not an ordinary equation with negligible coefficients for the variables. This equation has coefficients of 22 and 19! These are unusual numbers and they are not easily interchangeable the way that smaller coefficients would be. Additionally, the total value of souvenirs sold is just $161, meaning that there is not much room to trade t-shirts for caps. When you combine this fact with the large coefficients this means that there will be very few options for the values of T and C. And remember – you can’t buy 1/4 of a cap (even if your hat size is 71/4), so T and C must be integers. The “backdrop” of this problem adds substance to the shape of these puzzle pieces.
In order to determine if statement 1 is needed or if statement 2 is sufficient on its own, you could check to see whether or not statement 2 allows for different total numbers of souvenirs. For example, could Brian have sold fewer than 8 souvenirs? (The reason we start with 8 souvenirs is because we took a peek at statement 1. We are not relying on statement 1, we are just getting an idea that 8 souvenirs would be an acceptable total and we are looking for other acceptable totals).
So, what about 7 souvenirs? Could that total work? Actually, no. Even if we choose 7 of the more expensive souvenirs, the t-shirts, we find that 7*22 = $154. This is not enough money. We need the total value to be $161. So, we cannot have fewer than 8 total souvenirs. (The reason we cannot have ,say, 7.5 total souvenirs is that there is a hidden fact here and that is that you cannot have a portion of a T-shirt or a fraction of a cap. In other words we know that we must have integer values for T and C and for the total number of souvenirs as well).
What about having more than 8 souvenirs? If we try having 9 of the cheaper souvenirs we find that 9*19 = $171. That is too much money. Therefore we know that it is impossible to have more than 8 souvenirs, we must have exactly eight t-shirts and caps combined.
Statement 2 – the puzzle equation –provides us with a second hidden equation T + C = 8. This is the only information that statement 1 offers, therefore, we do not need statement 1. Statement 2 alone gives us both equations. And the correct answer is B.
If this were a problem solving question you could now use the two equations T + C = 8 and 22 T + 19 C = 161 to solve for the number of T-shirts that Brian sold. Since this is Data Sufficiency we do not need to solve it, however, we just need to get to the point where we are certain that we can solve it.
Before you choose answer choice C on a problem like this be sure to check for a puzzle equation – one that only fits together in just a single way. You might get two equations for the price of one. And remember this – Data Sufficiency problems are more often logic puzzles featuring numbers than they are just “math problems”. So the jigsaw analogy works – when you’re solving puzzles, pay particular attention to the way the pieces are put together!