In a row of 21 children facing North, Nitin is third to the right of Sita who is ninth from the right end of the row. What is Nitin's position from the left end?
16th
Solving Row Position Problems
Let's find Nitin's position from the left end in the row of 21 children.
Given Information:
- Total number of children in the row = 21
- Sita's position from the right end = 9th
- Nitin is third to the right of Sita.
- All children are facing North.
Finding Sita's Position from the Left End:
We are given Sita's position from the right end and the total number of children. We can find Sita's position from the left end using the formula:
Position from Left End = Total Number of Children - Position from Right End + 1
Substituting the given values:
Sita's position from Left End = \(21 - 9 + 1\)
Sita's position from Left End = \(12 + 1\)
Sita's position from Left End = \(13^{th}\)
So, Sita is at the 13th position from the left end of the row.
Finding Nitin's Position from the Left End:
Nitin is third to the right of Sita. Since the children are facing North, their right direction is towards the right end of the row, and their left direction is towards the left end of the row.
If Sita is at the 13th position from the left end, moving 3 positions to her right means moving 3 positions further towards the right end of the row. This means adding 3 to her position number from the left.
Nitin's position from Left End = Sita's position from Left End + 3
Nitin's position from Left End = \(13 + 3\)
Nitin's position from Left End = \(16^{th}\)
Conclusion:
Nitin is at the 16th position from the left end of the row.
Revision Table: Key Concepts in Row Arrangement
| Concept | Explanation | Formula (for a row of N people) |
|---|---|---|
| Position from Left | Position counted from the left end of the row. | - |
| Position from Right | Position counted from the right end of the row. | - |
| Total People (N) | Total count of individuals in the row. | Position from Left + Position from Right - 1 |
| Converting Position | Finding position from one end if position from the other end is known. | Position from Left = N - Position from Right + 1 Position from Right = N - Position from Left + 1 |
| Relative Position | Position of one person relative to another (e.g., to the right/left). | Depends on facing direction and relative distance. |
Additional Information on Relative Positioning
Understanding relative positions in row arrangement problems requires careful attention to the direction people are facing. This dictates how 'left' and 'right' are interpreted from an individual's perspective within the row.
- Facing North: If individuals are facing North, their right corresponds to the right end of the row, and their left corresponds to the left end of the row.
- Facing South: Conversely, if individuals are facing South, their right corresponds to the left end of the row, and their left corresponds to the right end of the row.
In this particular problem, since all children are facing North, Nitin being "third to the right of Sita" translates directly to his position number from the left end being three greater than Sita's position number from the left end.
It is essential to correctly interpret these directional cues based on the facing direction and the reference point (which end the position is measured from) to accurately solve row arrangement questions.
Important Questions from Rank Based
All 32 students in a class are standing in a row facing north. Akash is 12th from the right end while Priya is 18th from the left end. How many people are standing between Akash and Priya?
In a class of 36 students, the number of boys are twice the number of girls. In the class, there are 13 boys before Reema (girl) whose position is 19th in the class. How many girls are there in the class after Reema?
Selvam is on 9th position from upwards and on 38th position from downwards in a class. How many students are in class?
Six students, Abhay, Bhanu, Charu, David, Ekta and Farheen, are the top six rank holders in a school. The rank of Bhanu is between the ranks of Charu and David. Bhanu is on the fourth rank. There are two students between the ranks of Ekta and David. Ekta is at the lowest rank among all the given students. The rank of Abhay is immediately below the rank of Farheen. Who is on the fifth rank?
In a row of 35 students, Ramesh is at the 24th position from the beginning. The last two students left. What is Ramesh's position from the end of the row?
