\( \dfrac{1}{6!}+ \dfrac{1}{7!}= \dfrac{x}{8!}\)

= \( \dfrac{1}{6!}+ \dfrac{1}{7!\times 6!}= \dfrac{x}{8\times 7\times 6!}\)

= \( \dfrac{1}{6!}+ (1+\dfrac{1}{7!})= \dfrac{x}{8\times 7\times 6!}\)

= \( 1+\dfrac{1}{7}= \dfrac{x}{8\times 7}\)

= \(\dfrac{8}{7}= \dfrac{x}{8\times 7}\)

= \( \dfrac{8\times 8\times 7}{7}\)

= 64

Answered by Pragya Singh | 2 years agoHow many words each of 3 vowels and 2 consonants can be formed from the letters of the word INVOLUTE?

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