Question

10 men can complete a piece of work in 15 days and 15
women can complete the same work in 12 days. If all the
10 men and 15 women work together, in how many days
will the work get completed? 10 पुरुष 15 दिनों में एक काम पूरा कर
सकते हैं और 15 महिलाएं एक ही काम 12 दिनों में पूरा कर सकती हैं। यदि
सभी 10 पुरुष और 15 महिलाएं एक साथ काम करते हैं, तो कितने दिनों में
काम पूरा मिलेगा
a) 6
b) 6*1/3
c) 6*2/3
d) 7*2/3
​

Answer 1

Let the total work be ‘w’

Work done by 10 men in 15 days = w

Work done by 10 men in 1 day = w/15

Work done by 15 women in 12 days = w

Work done by 15 women in 1 day = w/12

Let the time taken to complete the work be ‘x’

So,

x[(w/15) + (w/12)] = w

x(1/15 + 1/12) = 1. (Dividing by ‘w’ on both sides)

x(1*5 + 1*4)/60 = 1. (Taking LCM)

=x(5 + 4) = 60

9x = 60

X = 60/9 = 20/3 = 6.67 days