Question

A and B can complete a work in 6 days.A can alone do it in 10 days. Then B can alone do the
work in how many days?
16 days
14 days
15 days

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Answer 1

GIVEN :-

• A and B can complete work in 6 days
• Work done by A alone is 10days

TO FIND :-

• Work done by B alone

SOLUTION:-

Let ,

Work done by B alone be x

So,

• One day work of A&B is $\dfrac{1}{6}$
• One day work of A is $\dfrac{1}{10}$
• One day work of B is $\dfrac{1}{x}$

One day work done by A&B together = one day work of A + one day work of B

$\dfrac{1}{6} = \dfrac{1}{10}+ \dfrac{1}{x}$

$\dfrac{1}{6} - \dfrac{1}{10} = \dfrac{1}{x}$

LCM OF 6, 10 is 30

$\dfrac{5 - 3}{30} = \dfrac{1}{x}$

$\dfrac{2}{30} = \dfrac{1}{x}$

$\dfrac{1}{15} = \dfrac{1}{x}$

One day work of b is 1/15

Total work done by b is 15

option (c)