Valmiki Ramayana Yuddha Kanda Sarga 75 Shloka 70
Original Shlokaवानरान्दशसप्तेतिराक्षसाजघ्नुराहवे । राक्षसान्दशसप्तेतिवानराश्चाभ्यपातयन् ।।6.75.70।।
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आहवे in that fight, राक्षसाः Rakshasas, दश ten, सप्त seven, इति like this, वानरान् Vanaras, जघ्नुः struck, वानराश्च Vanaras, राक्षसान् Rakshasas, दश ten, सप्त seven, इति like this, अभ्यपातयन् kept killing.
In that fight the Rakshasas killed the Vanaras at the rate of ten to seven and the Vanaras struck down Rakshasas at the rate of ten to seven.