Q1. Grids
MCQ · +3 / −1
Which of the following statements is correct?
- A) The ATM placed at the (R-C, V2) intersection has a cash requirement of Rs. 9 Lakhs.
- B) The cash requirement of the ATM placed at the (R-C, V2) intersection cannot be uniquely determined.
- C) The ATM placed at the (R-C, V2) intersection has a cash requirement of Rs. 8 Lakhs.
- D) There is no ATM placed at the (R-C, V2) intersection.
Correct Answer
A) The ATM placed at the (R-C, V2) intersection has a cash requirement of Rs. 9 Lakhs.
Step-by-step solution
📌 Core Concept
The row and column totals, together with the 12 km clue and the 7/15 extremes, fix every ATM value and position.
🔢 Step-by-Step Solution
1
The ATM at (R-C, V3) exists, and the only intersection 12 km from it is (R-B, V2): . So the second-highest ATM sits at (R-B, V2). Call it .
2
The six values are distinct and sum to . The minimum is 7 and the maximum is 15, so the other four sum to . Since is the second highest, .
3
V2 totals 21 and holds plus one other ATM, because two others would be too large. That other ATM has value .
4
R-B totals 20, so its other ATM has value , which must be at least 7. This rules out .
5
If , the values 13, 8 (V2), 7 (R-B) are forced, and the remaining two sum to 19, giving 9 and 10. The set is {7, 8, 9, 10, 13, 15}. R-A would need 22 from {8, 9, 10, 15}, which is impossible.
6
So . The V2 partner is 9, the R-B partner is 8, and the last value is . The set is {7, 8, 9, 11, 12, 15}.
7
R-B holds 12 and 8. The remaining {7, 9, 11, 15} split into R-A and R-C .
8
The V2 partner (9) must be in R-C, since R-A holds only 7 and 15. So (R-C, V2) is Rs. 9 Lakhs, and (R-C, V3) is 11.
Why Not the Others
B: the value is fixed at 9, so it is uniquely determined.
C: 8 is the R-B partner of 12, not the (R-C, V2) ATM.
D: R-C needs both 9 and 11, so (R-C, V2) must hold an ATM.
Correct Answer: A