Question

Arun is 20% more efficient than bala. in 72 days bala can complete a work. if they two are working together, in how many days the work can be completed?

Answer 1

answer is 38.4 days of tis question

Answer 2

Answer: The number of days the work to be done together is given by $32\frac{2}{11}\ days$

Step-by-step explanation:

Since we have given that

Arun is 20% more efficient than Bala.

So, Let the efficiency of Bala be 100

So, the efficiency of Arun be 120

Ratio of their efficiency of Bala to Arun is given by

$100:120\\\\\implies 5:6$

Since we know that the ratio of efficiency is always reciprocal of their ratio of number of day or time.

So, Ratio of their time is given by

$6:5$

So, According to question,

$6x=72\\\\x=12$

Number of days taken by Arun is given by

$5x=5\times 12=60\ days$

so, Amount of  work to be done together is given by

$\frac{1}{72}+\frac{1}{60}\\\\=\frac{5+6}{360}\\\\=\frac{11}{360}$

so, the number of days the work to be done together is given by

$\frac{360}{11}=32\frac{2}{11}\ days$