Valmiki Ramayana Kishkindha Kanda Sarga 52 Shloka 13
Original Shlokaसाध्वत्र प्रविशामेति मया तूक्ताः प्लवङ्गमाः। तेषामपि हि सर्वेषामनुमानमुपागतम्।।4.52.13।।
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अत्र here, साधु it is proper, प्रविशाम let us enter, इति thus, मया by me, प्लवङ्गमाः monkeys, उक्ताः have been told, तेषाम् for them, सर्वेषामपि for all of them, अनुमानम् inferring, उपागतम् came in.
'I suggested to the fellowmonkeys to enter this cave, inferring that there would be water and all of them came to the same conclusion.