A group of 202 people went on an overnight camping trip, taking 60 tents with them. Some of the tents held 2 people each, and the rest held 4 people each. Assuming all the tents were filled to capacity and every person got to sleep in a tent, exactly how many of the tents were 2-person tents?

Explanation

Choice C is correct. Let x represent the number of 2-person tents and let y represent the number of 4-person tents. It is given that the total number of tents was 60 and the total number of people in the group was 202. This situation can be expressed as a system of two equations, x + y = 60 and 2x + 4y = 202. The first equation can be rewritten as y = −x + 60. Substituting −x + 60 for y in the equation 2x + 4y = 202 yields 2x + 4(−x + 60) = 202. Distributing and combining like terms gives −2x + 240 = 202. Subtracting 240 from both sides of −2x + 240 = 202 and then dividing both sides by −2 gives x = 19. Therefore, the number of 2-person tents is 19.Alternate approach: If each of the 60 tents held 4 people, the total number of people that could be accommodated in tents would be 240. However, the actual number of people who slept in tents was 202. The difference of 38 accounts for the 2-person tents. Since each of these tents holds 2 people fewer than a 4-person tent, 38/2 = 19 gives the number of 2-person tents.