UPSC Prelims 2025 CSAT Paper II · Q80 of 78 Logical Reasoning medium

Three teams P, Q, R participated in a tournament in which the teams play with one another exactly once. A win fetches a team 2 points and a draw 1 point. A team gets no point for a loss. Each team scored exactly one goal in the tournament. The team P got 3 points, Q got 2 points and R got 1 point. Which of the following statements is/are correct ? I. The result of the match between P and Q is a draw with the score 0 – 0. II. The number of goals scored by R against Q is 1. Which of the statements given above is/are correct ?

  1. (a) I only
  2. (b) II only
  3. (c) Both I and II ✓ UPSC's answer
  4. (d) Neither I nor II

Why the answer is (c)

• There are 3 matches in total (P vs Q, Q vs R, R vs P), and each team scored exactly one goal, meaning the total goals in the tournament is 3.

• Since P has 3 points, P must have won one match (2 points) and drawn one match (1 point), as a loss would yield 0 points and two wins would yield 4 points.

• Q has 2 points, which implies Q won one match and lost one match (2+0), or drew two matches (1+1). However, if Q drew two matches, P and R would also have draws, conflicting with P's 3 points (win+draw) and R's 1 point (draw+loss or 3 losses). Let's analyze the points distribution: Total points = 3+2+1 = 6. Each match distributes 2 points (win/loss) or 2 points (draw/draw). Thus, all 3 matches must be decisive (no draws) OR some draws exist. Wait, a draw gives 1+1=2 points. A win/loss gives 2+0=2 points. So total points is always 6. This doesn't restrict draws yet.

• Let's look at goals. Each team scored 1 goal. Total goals = 3. This means there are no 0-0 draws because a 0-0 draw contributes 0 goals. If a match is a draw, it must be 1-1 (contributing 2 goals) or 0-0 (0 goals). Since total goals is 3, we cannot have a 1-1 draw (would use 2 goals, leaving 1 for two other matches, impossible as goals are integers and min 0). We cannot have a 0-0 draw if it's the only draw? Let's check. If P vs Q is 0-0, that's 0 goals. Remaining goals = 3. Q vs R and R vs P must account for 3 goals. Points: P=3, Q=2, R=1.

• If P vs Q is 0-0 (Draw), P gets 1, Q gets 1. P needs 2 more points from R. So P beats R (2 pts). P total = 3. Q has 1 pt, needs 1 more from R. So Q draws with R? If Q draws with R, Q total = 2. R gets 1 from P loss (0) and 1 from Q draw (1). R total = 1. This fits the points: P(3), Q(2), R(1).

• Now check goals for this scenario: P vs Q is 0-0. P beats R. Q draws R. Goals: P scored 1 total. In P vs Q (0-0), P scored 0. So P must have scored 1 in P vs R. Q scored 1 total. In P vs Q (0-0), Q scored 0. So Q must have scored 1 in Q vs R. R scored 1 total. In P vs R, R scored 0 (since P won and P scored 1, if R scored 1 it would be 1-1 draw, but P won). So R must have scored 1 in Q vs R. But Q vs R is a draw. If Q scored 1 and R scored 1, the score is 1-1. This is a valid draw. Total goals: P(1) + Q(1) + R(1) = 3. Matches: P-Q (0-0), P-R (1-0), Q-R (1-1). This scenario is consistent.

• Statement I says P vs Q is a draw with score 0-0. In our derived scenario, this is true.

• Statement II says R scored 1 goal against Q. In our derived scenario, Q vs R is 1-1, so R scored 1 goal against Q. This is true.

• Are there other scenarios? If P vs Q is not 0-0. Suppose P vs Q is a win/loss. P wins (2 pts). P needs 1 more from R, so P draws R. Q has 0 from P, needs 2 from R, so Q beats R. Points: P(2+1=3), Q(0+2=2), R(0+0=0). But R has 1 point. Contradiction. Suppose Q wins P. Q(2), P(0). P needs 3 from R, impossible (max 2). So P must win or draw Q. If P draws Q (1-1), P(1), Q(1). P needs 2 from R (Win). Q needs 1 from R (Draw). R gets 0 from P, 1 from Q. R total 1. Points fit. Goals: P-Q is 1-1. P scored 1, Q scored 1. P has 0 goals left for P-R. Q has 0 goals left for Q-R. R must score 1 goal total. In P-R (P wins), if P scored 0, R must score 0 for P to win? No, P wins means P > R. If P scored 0, R must score negative, impossible. So P must score > R. If P scored 0 in P-Q, P must score 1 in P-R. But P already scored 1 in P-Q (1-1). Total P goals = 2. Contradiction (P scored exactly 1). Thus, P-Q cannot be 1-1. The only valid draw for P-Q is 0-0.

Why the other options are wrong

(a) I only
Statement II is also correct, so 'I only' is incomplete.
(b) II only
Statement I is also correct, so 'II only' is incomplete.
(d) Neither I nor II
Both statements I and II are correct based on the unique solution derived from the points and goal constraints.

Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2025, held on 25 May 2025. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.

Reading the answer is not the same as getting it right under a clock. Practise this question with UPSC's negative marking, and anything you miss goes into an error notebook until you get it right twice.

Practise this paper free