Midrash for Chullin 195:27

רבי יעקב בר אידי ורבי שמואל בר נחמני תרוייהו משמיה דרבי יהושע בן לוי אמרי

Then I might just as well be satisfied with forty-five-fold.<span class="x" onmousemove="('comment',' Since in this and in the following cases the amount of forbidden substance was less than the minimum legal quantity, the standard of sixty-fold is not rigidly adhered to but smaller standards e.g., of forty-seven-fold, forty-five-fold and forty-three-fold would suffice to render the mixture permitted. According to another interpretation in Rashi the reverse decision is arrived at thus: 'My father did not adopt a standard of forty-seven-fold, shall I then permit by the standard of forty-five-fold'? The case, accordingly, was of an entire olive's bulk that was cooked with permitted food.');">¹⁰</span>

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