Question

In a row of girl students facing north, Radhika is 10th to the left of Purnima who is 21th from the right end. If Monika who is 17th from the left end is 4th to the right of Radhika, how many students are there in the row?

• A. 37
• B. 44
• C. 43
• D. Data is insufficient

Answer 1

The Correct Option is C

To determine how many students are in the row, we need to use the information provided to map out the positions of Radhika, Purnima, and Monika and apply logical reasoning.

1. Purnima is 21st from the right end. Hence, her position from the right is known.
2. Radhika is 10th to the left of Purnima. Since Purnima is 21st from the right: 
   \(Radhika's\ position\ from\ the\ right = 21 + 10 = 31\)
3. Monika is 17th from the left end and is 4th to the right of Radhika. Thus: 
   \(Radhika's\ position\ from\ the\ left = 17 - 4 = 13\)
4. Now, we know Radhika's position from both ends, allowing us to find the total number of students: 
   \(Total\ number\ of\ students = \ Radhika's\ position\ from\ the\ left\ +\ Radhika's\ position\ from\ the\ right\ - 1 = 13 + 31 - 1 = 43\)

Therefore, there are 43 students in the row. The correct answer is 43.

Answer 2

The total number of students in the row is 43. Here's how:

• Purnima is 21 from the right, so her position from the left is N−20N - 20N−20.
• Radhika is 10 to the left of Purnima, so her position is N−30N - 30N−30.
• Monika is 4 to the right of Radhika, so her position is N−26N - 26N−26.
• Monika is 17 from the left, so N−26=17N - 26 = 17N−26=17.
• Solving gives N=43N = 43N=43.

Therefore, there are 43 students in the row.