And the saṃkhyā-s ending with the affix ḍati are called ṣaṭ,
This sutra enlarges the scope of the definition of षट् by including in it, words formed by डति. By sutra 22, words in डति are already sankhya; by this they are also षट्. Therefore we have कति पठन्ति, 'how many are reading,' कति पश्य 'see how many.' Here कति has lost its plural termination by 7.1.22.,