Seven friends stand in a row facing north. From the left end they are Asha, Bilal, Chetan, Devika, Esha, Firoz and Gauri. First Asha and Esha interchange places. Then Bilal interchanges places with whoever is at the right end. Finally, whoever is exactly in the middle of the row interchanges places with whoever is 2nd from the left. Who is now exactly in the middle of the row?

GauriCorrect answerYour answerDevikaCorrect answerYour answerAshaCorrect answerYour answerBilalCorrect answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer A

Correct answer: A

After Asha and Esha swap: Esha, Bilal, Chetan, Devika, Asha, Firoz, Gauri.
Bilal swaps with the right end, Gauri: Esha, Gauri, Chetan, Devika, Asha, Firoz, Bilal.
The middle (4th) is Devika and 2nd from the left is Gauri; they swap: Esha, Devika, Chetan, Gauri, Asha, Firoz, Bilal.
The 4th place now holds Gauri.

Worth noting

Devika is the answer if the last swap is skipped. Write the whole row after every swap; the people at 'the right end' and 'the middle' change as you go.

Concept: Several interchanges tracked on the whole row
Typical timeTypical: 115 s
Your timeYours: —

The rule this testsInterchanged positions

Practise this chapter →

Ten questions from Ranking and Ordering, at your own pace.

Explanation