Question

a can do a work in 10 days b can do the same work in 20 days they do work together a leaves 2 days before the completion of work how many days it take to complete the work​

Answer 1

Given :

A can do a work in 10 days B can do the same work in 20 days they do work together a leaves 2 days before the completion of work.

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To find :

How many days it take to complete the work.

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Solution :

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Let the required days be x

A works for ( x - 2 ) days, while B works for x days.

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According to the Question

$\: \: \: : \implies\sf \dfrac{x - 2}{10} + \dfrac{x}{20} = 1$

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$\: \: \: :\implies\sf {2x - 4 + x = 20}$

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$\: \: \: : \implies \sf 3x = 24$

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$\large \blue \star \: \boxed {\red{\tt{x = 8 \: days}}} \: \blue\star$