Question

7. 'A' takes 12 days to complete a work. 'B' takes 15 days to complete the same work. If they work together, how many days they will take to complete the same work?​

Answer 1

Answer:

5 days

Step-by-step explanation:

Let x be the number of extra days

Work rate for A =W/12

Work rate for B = W/15

Now...

W/12 (3+x) +W/15x =W

3+x/12 + x/15 =1

therefore : x =5

Answer 2

Answer:

$\huge \dag{\boxed{\underline{\underline{\mathbb \purple{HRU?}}}}}$

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$\huge{\underline{\mathfrak \purple{Question}}}$

A' takes 12 days to complete a work. 'B' takes 15 days to complete the same work. If they work together, how many days they will take to complete the same work?

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$\huge{\underline{\mathfrak \purple{Answer}}}$

Let us find the Work rate

$(\implies{\tt{\frac{W}{Days/Time}}})$

Now, let us assume $x$ to be number of Extra Days.

(i) For A = $\tt{\frac{W}{12}}$

(ii) For B = $\tt{\frac{W}{15}}$

$\implies{\tt \red{\frac{W}{12}(3 + x) + \frac{W}{15}x => W}}$

$\implies{\tt \green{\frac{3 + x}{12} + \frac{x}{15} = 1}}$

$\boxed{\underline{\implies{\tt \purple{x = 15}}}}$

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HOPES IT HELPS!:)