CAT 2023 Slot 1 · DILR · Set 3: Restaurant Ratings of Gig Workers

The full set and all 5 questions (Q11–Q15) from CAT 2023 Slot 1, with answers and solutions.

Five restaurants, coded R1, R2, R3, R4 and R5 gave integer ratings to five gig workers - Ullas, Vasu, Waman, Xavier and Yusuf, on a scale of 1 to 5.

The means of the ratings given by R1, R2, R3, R4 and R5 were 3.4, 2.2, 3.8, 2.8 and 3.4 respectively.

The summary statistics of these ratings for the five workers is given below.

Ullas

Vasu

Waman

Xavier

Yusuf

Mean rating

2.2

3.8

3.4

3.6

2.6

Median rating

2

4

4

4

3

Modal rating

2

4

5

5

1 and 4

Range of rating*

3

3

4

4

3

* Range of ratings is defined as the difference between the maximum and minimum ratings awarded to a worker.

The following is partial information about ratings of 1 and 5 awarded by the restaurants to the workers.

(a) R1 awarded a rating of 5 to Waman, as did R2 to Xavier, R3 to Waman and Xavier, and R5 to Vasu.

(b) R1 awarded a rating of 1 to Ullas, as did R2 to Waman and Yusuf, and R3 to Yusuf.

Question 11 · Caselet DI

How many individual ratings cannot be determined from the above information?
Answer & solution

Answer: 0

Solving the set

Step 1 – Each worker's five ratings. Sum = 5 × mean. Use the median, mode, range and the known 1s and 5s.

• Ullas: sum 11, has a 1 (R1), range 3 ⇒ maximum 4. Median 2 and mode 2 ⇒ 1, 2, 2, x, 4 with 1 + 2 + 2 + x + 4 = 11 ⇒ x = 2.

• Vasu: sum 19, has a 5 (R5), range 3 ⇒ minimum 2. Median 4 ⇒ 2, a, 4, b, 5 with a + b = 8 ⇒ a = b = 4.

• Waman: sum 17, two 5s (R1, R3) and a 1 (R2), median 4 ⇒ 1, x, 4, 5, 5 with x = 2.

• Xavier: sum 18, two 5s (R2, R3), range 4 ⇒ minimum 1. Median 4 ⇒ 1, x, 4, 5, 5 with x = 3.

• Yusuf: sum 13, two 1s (R2, R3), modes 1 and 4, median 3 ⇒ 1, 1, 3, 4, 4.

Worker

Sum (5 × mean)

Known 1s/5s

Ratings (from median, mode, range)

Ullas

11

1 (R1)

1, 2, 2, 2, 4

Vasu

19

5 (R5)

2, 4, 4, 4, 5

Waman

17

5 (R1, R3), 1 (R2)

1, 2, 4, 5, 5

Xavier

18

5 (R2, R3)

1, 3, 4, 5, 5

Yusuf

13

1 (R2, R3)

1, 1, 3, 4, 4

Step 2 – Restaurant totals (5 × mean): R1 = 17, R2 = 11, R3 = 19, R4 = 14, R5 = 17.

• R2: Waman 1 + Xavier 5 + Yusuf 1 = 7, so Ullas + Vasu = 4. Both are at least 2, so both are 2. Vasu's single 2 is at R2, so Vasu gets 4 from R1, R3 and R4.

• R3: Vasu 4 + Waman 5 + Xavier 5 + Yusuf 1 = 15, so Ullas = 4. Ullas then gets 2 from R4 and R5.

• R1: Ullas 1 + Vasu 4 + Waman 5 = 10, so Xavier + Yusuf = 7: (3, 4) or (4, 3).

• If Xavier = 4 and Yusuf = 3 at R1, Yusuf has 4 at both R4 and R5. R4 needs Waman + Xavier = 14 − 2 − 4 − 4 = 4, but Waman's options (2 or 4) and Xavier's (1 or 3) never add to 4. Not possible.

• So Xavier = 3 and Yusuf = 4 at R1. R4 needs Waman + Xavier + Yusuf = 8: only 4 + 1 + 3 works. R5 then gets Waman 2, Xavier 4, Yusuf 4 (total 17 ✓).

Restaurant

Ullas

Vasu

Waman

Xavier

Yusuf

Sum

Mean

R1

1

4

5

3

4

17

3.4

R2

2

2

1

5

1

11

2.2

R3

4

4

5

5

1

19

3.8

R4

2

4

4

1

3

14

2.8

R5

2

5

2

4

4

17

3.4

This question

The grid in Step 2 is completely determined. So no rating is undetermined.

Hence, the answer is 0.

Question 12 · Caselet DI

To how many workers did R2 give a rating of 4?
Answer & solution

Answer: 0

Solving the set

Step 1 – Each worker's five ratings. Sum = 5 × mean. Use the median, mode, range and the known 1s and 5s.

• Ullas: sum 11, has a 1 (R1), range 3 ⇒ maximum 4. Median 2 and mode 2 ⇒ 1, 2, 2, x, 4 with 1 + 2 + 2 + x + 4 = 11 ⇒ x = 2.

• Vasu: sum 19, has a 5 (R5), range 3 ⇒ minimum 2. Median 4 ⇒ 2, a, 4, b, 5 with a + b = 8 ⇒ a = b = 4.

• Waman: sum 17, two 5s (R1, R3) and a 1 (R2), median 4 ⇒ 1, x, 4, 5, 5 with x = 2.

• Xavier: sum 18, two 5s (R2, R3), range 4 ⇒ minimum 1. Median 4 ⇒ 1, x, 4, 5, 5 with x = 3.

• Yusuf: sum 13, two 1s (R2, R3), modes 1 and 4, median 3 ⇒ 1, 1, 3, 4, 4.

Worker

Sum (5 × mean)

Known 1s/5s

Ratings (from median, mode, range)

Ullas

11

1 (R1)

1, 2, 2, 2, 4

Vasu

19

5 (R5)

2, 4, 4, 4, 5

Waman

17

5 (R1, R3), 1 (R2)

1, 2, 4, 5, 5

Xavier

18

5 (R2, R3)

1, 3, 4, 5, 5

Yusuf

13

1 (R2, R3)

1, 1, 3, 4, 4

Step 2 – Restaurant totals (5 × mean): R1 = 17, R2 = 11, R3 = 19, R4 = 14, R5 = 17.

• R2: Waman 1 + Xavier 5 + Yusuf 1 = 7, so Ullas + Vasu = 4. Both are at least 2, so both are 2. Vasu's single 2 is at R2, so Vasu gets 4 from R1, R3 and R4.

• R3: Vasu 4 + Waman 5 + Xavier 5 + Yusuf 1 = 15, so Ullas = 4. Ullas then gets 2 from R4 and R5.

• R1: Ullas 1 + Vasu 4 + Waman 5 = 10, so Xavier + Yusuf = 7: (3, 4) or (4, 3).

• If Xavier = 4 and Yusuf = 3 at R1, Yusuf has 4 at both R4 and R5. R4 needs Waman + Xavier = 14 − 2 − 4 − 4 = 4, but Waman's options (2 or 4) and Xavier's (1 or 3) never add to 4. Not possible.

• So Xavier = 3 and Yusuf = 4 at R1. R4 needs Waman + Xavier + Yusuf = 8: only 4 + 1 + 3 works. R5 then gets Waman 2, Xavier 4, Yusuf 4 (total 17 ✓).

Restaurant

Ullas

Vasu

Waman

Xavier

Yusuf

Sum

Mean

R1

1

4

5

3

4

17

3.4

R2

2

2

1

5

1

11

2.2

R3

4

4

5

5

1

19

3.8

R4

2

4

4

1

3

14

2.8

R5

2

5

2

4

4

17

3.4

This question

From the grid, R2 gave 2 (Ullas), 2 (Vasu), 1 (Waman), 5 (Xavier) and 1 (Yusuf). No worker got a 4 from R2.

Hence, the answer is 0.

Question 13 · Caselet DI

What rating did R1 give to Xavier?
Answer & solution

Answer: 3

Solving the set

Step 1 – Each worker's five ratings. Sum = 5 × mean. Use the median, mode, range and the known 1s and 5s.

• Ullas: sum 11, has a 1 (R1), range 3 ⇒ maximum 4. Median 2 and mode 2 ⇒ 1, 2, 2, x, 4 with 1 + 2 + 2 + x + 4 = 11 ⇒ x = 2.

• Vasu: sum 19, has a 5 (R5), range 3 ⇒ minimum 2. Median 4 ⇒ 2, a, 4, b, 5 with a + b = 8 ⇒ a = b = 4.

• Waman: sum 17, two 5s (R1, R3) and a 1 (R2), median 4 ⇒ 1, x, 4, 5, 5 with x = 2.

• Xavier: sum 18, two 5s (R2, R3), range 4 ⇒ minimum 1. Median 4 ⇒ 1, x, 4, 5, 5 with x = 3.

• Yusuf: sum 13, two 1s (R2, R3), modes 1 and 4, median 3 ⇒ 1, 1, 3, 4, 4.

Worker

Sum (5 × mean)

Known 1s/5s

Ratings (from median, mode, range)

Ullas

11

1 (R1)

1, 2, 2, 2, 4

Vasu

19

5 (R5)

2, 4, 4, 4, 5

Waman

17

5 (R1, R3), 1 (R2)

1, 2, 4, 5, 5

Xavier

18

5 (R2, R3)

1, 3, 4, 5, 5

Yusuf

13

1 (R2, R3)

1, 1, 3, 4, 4

Step 2 – Restaurant totals (5 × mean): R1 = 17, R2 = 11, R3 = 19, R4 = 14, R5 = 17.

• R2: Waman 1 + Xavier 5 + Yusuf 1 = 7, so Ullas + Vasu = 4. Both are at least 2, so both are 2. Vasu's single 2 is at R2, so Vasu gets 4 from R1, R3 and R4.

• R3: Vasu 4 + Waman 5 + Xavier 5 + Yusuf 1 = 15, so Ullas = 4. Ullas then gets 2 from R4 and R5.

• R1: Ullas 1 + Vasu 4 + Waman 5 = 10, so Xavier + Yusuf = 7: (3, 4) or (4, 3).

• If Xavier = 4 and Yusuf = 3 at R1, Yusuf has 4 at both R4 and R5. R4 needs Waman + Xavier = 14 − 2 − 4 − 4 = 4, but Waman's options (2 or 4) and Xavier's (1 or 3) never add to 4. Not possible.

• So Xavier = 3 and Yusuf = 4 at R1. R4 needs Waman + Xavier + Yusuf = 8: only 4 + 1 + 3 works. R5 then gets Waman 2, Xavier 4, Yusuf 4 (total 17 ✓).

Restaurant

Ullas

Vasu

Waman

Xavier

Yusuf

Sum

Mean

R1

1

4

5

3

4

17

3.4

R2

2

2

1

5

1

11

2.2

R3

4

4

5

5

1

19

3.8

R4

2

4

4

1

3

14

2.8

R5

2

5

2

4

4

17

3.4

This question

From Step 2, R1 gave Xavier a rating of 3.

Hence, the answer is 3.

Question 14 · Caselet DI

What is the median of the ratings given by R3 to the five workers?
Answer & solution

Answer: 4

Solving the set

Step 1 – Each worker's five ratings. Sum = 5 × mean. Use the median, mode, range and the known 1s and 5s.

• Ullas: sum 11, has a 1 (R1), range 3 ⇒ maximum 4. Median 2 and mode 2 ⇒ 1, 2, 2, x, 4 with 1 + 2 + 2 + x + 4 = 11 ⇒ x = 2.

• Vasu: sum 19, has a 5 (R5), range 3 ⇒ minimum 2. Median 4 ⇒ 2, a, 4, b, 5 with a + b = 8 ⇒ a = b = 4.

• Waman: sum 17, two 5s (R1, R3) and a 1 (R2), median 4 ⇒ 1, x, 4, 5, 5 with x = 2.

• Xavier: sum 18, two 5s (R2, R3), range 4 ⇒ minimum 1. Median 4 ⇒ 1, x, 4, 5, 5 with x = 3.

• Yusuf: sum 13, two 1s (R2, R3), modes 1 and 4, median 3 ⇒ 1, 1, 3, 4, 4.

Worker

Sum (5 × mean)

Known 1s/5s

Ratings (from median, mode, range)

Ullas

11

1 (R1)

1, 2, 2, 2, 4

Vasu

19

5 (R5)

2, 4, 4, 4, 5

Waman

17

5 (R1, R3), 1 (R2)

1, 2, 4, 5, 5

Xavier

18

5 (R2, R3)

1, 3, 4, 5, 5

Yusuf

13

1 (R2, R3)

1, 1, 3, 4, 4

Step 2 – Restaurant totals (5 × mean): R1 = 17, R2 = 11, R3 = 19, R4 = 14, R5 = 17.

• R2: Waman 1 + Xavier 5 + Yusuf 1 = 7, so Ullas + Vasu = 4. Both are at least 2, so both are 2. Vasu's single 2 is at R2, so Vasu gets 4 from R1, R3 and R4.

• R3: Vasu 4 + Waman 5 + Xavier 5 + Yusuf 1 = 15, so Ullas = 4. Ullas then gets 2 from R4 and R5.

• R1: Ullas 1 + Vasu 4 + Waman 5 = 10, so Xavier + Yusuf = 7: (3, 4) or (4, 3).

• If Xavier = 4 and Yusuf = 3 at R1, Yusuf has 4 at both R4 and R5. R4 needs Waman + Xavier = 14 − 2 − 4 − 4 = 4, but Waman's options (2 or 4) and Xavier's (1 or 3) never add to 4. Not possible.

• So Xavier = 3 and Yusuf = 4 at R1. R4 needs Waman + Xavier + Yusuf = 8: only 4 + 1 + 3 works. R5 then gets Waman 2, Xavier 4, Yusuf 4 (total 17 ✓).

Restaurant

Ullas

Vasu

Waman

Xavier

Yusuf

Sum

Mean

R1

1

4

5

3

4

17

3.4

R2

2

2

1

5

1

11

2.2

R3

4

4

5

5

1

19

3.8

R4

2

4

4

1

3

14

2.8

R5

2

5

2

4

4

17

3.4

This question

R3 gave 4, 4, 5, 5, 1. Arranged in order: 1, 4, 4, 5, 5. The median is 4.

Hence, the answer is 4.

Question 15 · Caselet DI

Which among the following restaurants gave its median rating to exactly one of the workers?
  1. A
    R2
  2. B
    R5
  3. C
    R4
  4. D
    R3
Pick an option, then check.
Answer & solution

Answer: Option C

Solving the set

Step 1 – Each worker's five ratings. Sum = 5 × mean. Use the median, mode, range and the known 1s and 5s.

• Ullas: sum 11, has a 1 (R1), range 3 ⇒ maximum 4. Median 2 and mode 2 ⇒ 1, 2, 2, x, 4 with 1 + 2 + 2 + x + 4 = 11 ⇒ x = 2.

• Vasu: sum 19, has a 5 (R5), range 3 ⇒ minimum 2. Median 4 ⇒ 2, a, 4, b, 5 with a + b = 8 ⇒ a = b = 4.

• Waman: sum 17, two 5s (R1, R3) and a 1 (R2), median 4 ⇒ 1, x, 4, 5, 5 with x = 2.

• Xavier: sum 18, two 5s (R2, R3), range 4 ⇒ minimum 1. Median 4 ⇒ 1, x, 4, 5, 5 with x = 3.

• Yusuf: sum 13, two 1s (R2, R3), modes 1 and 4, median 3 ⇒ 1, 1, 3, 4, 4.

Worker

Sum (5 × mean)

Known 1s/5s

Ratings (from median, mode, range)

Ullas

11

1 (R1)

1, 2, 2, 2, 4

Vasu

19

5 (R5)

2, 4, 4, 4, 5

Waman

17

5 (R1, R3), 1 (R2)

1, 2, 4, 5, 5

Xavier

18

5 (R2, R3)

1, 3, 4, 5, 5

Yusuf

13

1 (R2, R3)

1, 1, 3, 4, 4

Step 2 – Restaurant totals (5 × mean): R1 = 17, R2 = 11, R3 = 19, R4 = 14, R5 = 17.

• R2: Waman 1 + Xavier 5 + Yusuf 1 = 7, so Ullas + Vasu = 4. Both are at least 2, so both are 2. Vasu's single 2 is at R2, so Vasu gets 4 from R1, R3 and R4.

• R3: Vasu 4 + Waman 5 + Xavier 5 + Yusuf 1 = 15, so Ullas = 4. Ullas then gets 2 from R4 and R5.

• R1: Ullas 1 + Vasu 4 + Waman 5 = 10, so Xavier + Yusuf = 7: (3, 4) or (4, 3).

• If Xavier = 4 and Yusuf = 3 at R1, Yusuf has 4 at both R4 and R5. R4 needs Waman + Xavier = 14 − 2 − 4 − 4 = 4, but Waman's options (2 or 4) and Xavier's (1 or 3) never add to 4. Not possible.

• So Xavier = 3 and Yusuf = 4 at R1. R4 needs Waman + Xavier + Yusuf = 8: only 4 + 1 + 3 works. R5 then gets Waman 2, Xavier 4, Yusuf 4 (total 17 ✓).

Restaurant

Ullas

Vasu

Waman

Xavier

Yusuf

Sum

Mean

R1

1

4

5

3

4

17

3.4

R2

2

2

1

5

1

11

2.2

R3

4

4

5

5

1

19

3.8

R4

2

4

4

1

3

14

2.8

R5

2

5

2

4

4

17

3.4

This question

Restaurant

Ratings in order

Median

Workers given the median

R2

1, 1, 2, 2, 5

2

2 (Ullas, Vasu)

R3

1, 4, 4, 5, 5

4

2 (Ullas, Vasu)

R4

1, 2, 3, 4, 4

3

1 (Yusuf)

R5

2, 2, 4, 4, 5

4

2 (Xavier, Yusuf)

R4's median is 3 and only Yusuf got a 3 from R4.

Hence, the answer is option 3.

Take this paper as a timed test
Real exam timing, instant score, rank and topic-wise analysis.

Practice timed →