In a row of children, Bhavana is ninth from the left and Ashu is thirteenth…
2018
In a row of children, Bhavana is ninth from the left and Ashu is thirteenth from the right. They exchange their positions and then Bhavana becomes seventeenth from the left. Find the new position of Ashu from the right end of the row.
- A.
21st
- B.
22nd
- C.
23rd
- D.
20th
Attempted by 173 students.
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Correct answer: A
Bhavana is 9th from the left. Ashu is 13th from the right, so Ashu's initial position from the left = N - 13 + 1 = N - 12.
They swap positions. After swapping Bhavana becomes 17th from the left, so Bhavana's new position (which was Ashu's initial position) equals 17: N - 12 = 17.
Solve for N: N - 12 = 17 → N = 29. So there are 29 children in the row.
After the swap Ashu occupies Bhavana's original position, which is 9th from the left. Convert this to position from the right: position from right = N - left_position + 1 = 29 - 9 + 1 = 21.
Therefore Ashu's new position from the right end is 21st (21वीं).