Valmiki Ramayana Sundara Kanda Sarga 43 Shloka 22
Original Shlokaदशनागबलाः केचित्केचिद्दशगुणोत्तराः। केचिन्नागसहस्रस्य बभूवुस्तुल्यविक्रमाः।।5.43.22।।
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केचित् some, दशनागबलाः have ten elephants strength, केचित् some, दशगुणोत्तराः ten hundred elephants strength, केचित् some, नागसहस्रस्य thousand elephants strength, तुल्यविक्रमाः equal in power, बभूवुः will be.
"Of them some have the strength equal to ten elephants, others are ten times stronger, and still others have a thousand elephants' strength.