Valmiki Ramayana Yuddha Kanda Sarga 41 Shloka 47
Original Shlokaदशनागबलाःकेचित्केचिद्धशगुणोत्तराः ।।6.41.47।। केचिन्नागसहस्रस्यबभूवुस्तुल्यविक्रमाः ।
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केचित् a few, दशनागबलाः strength of ten elephants, केचित् some, दशगुणोत्तराः ten times more strong than others, केचित् a few, नागसहस्रस्य equal to thousand elephants in strength, तुल्यविक्रमाः endowed with great strength, बभूवुः were.
A few of them were having the strength of ten elephants, some had ten times more than others, and a few were endowed with great strength equal to thousand elephants.