A word arrangement machine, when given an input line of words, rearranges them step by step following a particular rule. An illustration of an input and its rearrangement is given below.
Input: sky bell rain door wind lake hill moon
Step I: moon bell rain door wind lake hill sky
Step II: moon hill rain door wind lake bell sky
Step III: moon hill lake door wind rain bell sky
Step IV: moon hill lake wind door rain bell sky
Step IV is the last step of this input.
Input: coin harp nest jug kite oven pen rice
Following the same rule, which of the following will be Step III for this input?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → rice pen oven jug kite nest harp coin
Compare each step of the illustration with the one before it. The machine works by places, not by the words: Step I interchanges the 1st and the last word, Step II the 2nd word from each end, Step III the 3rd word from each end, and so on.
Step I: the words in the first place from the left (sky) and the first place from the right (moon) change places
Step II: the words in the second place from the left (bell) and the second place from the right (hill) change places
Step III: the words in the third place from the left (rain) and the third place from the right (lake) change places
Step IV: the words in the fourth place from the left (door) and the fourth place from the right (wind) change places
After Step IV every pair of places from the two ends has been interchanged, so the arrangement is complete.
Apply the same rule to the input coin harp nest jug kite oven pen rice.
Step I: the words in the first place from the left (coin) and the first place from the right (rice) change places, giving rice harp nest jug kite oven pen coin
Step II: the words in the second place from the left (harp) and the second place from the right (pen) change places, giving rice pen nest jug kite oven harp coin
Step III: the words in the third place from the left (nest) and the third place from the right (oven) change places, giving rice pen oven jug kite nest harp coin
So Step III is rice pen oven jug kite nest harp coin.
Why the other options are incorrect
Option (1) rice pen nest jug kite oven harp coin — Incorrect. This is Step II; the third words from each end have not yet changed places.
Option (2) rice pen oven kite jug nest harp coin — Incorrect. This is Step IV, where the fourth words from each end have also changed places.
Option (3) coin harp oven jug kite nest pen rice — Incorrect. Here only the third words from each end change places in the input; each step works on the step before it, so Steps I and II come first.