Find x in $$\dfrac{ 1}{6!} + \dfrac{1}{7!} =\dfrac{ x}{8!}$$

Asked by Aaryan | 1 year ago |  60

##### Solution :-

We know that

8! = 8 × 7 × 6!

7! = 7 × 6!

So by using these values,

$$\dfrac{ x}{6!}+\dfrac{ x}{7!} =\dfrac{ x}{8!}$$

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

$$\dfrac{ 8}{7! }= \dfrac{x}{(8×7!)}$$

x = $$\dfrac{ (8 × 8 × 7!)}{7!}$$

= 8 × 8

= 64

The value of x is 64.

Answered by Aaryan | 1 year ago

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