4 men&6women finish a job in 8days, while 3men&7women finish it in 10 days. In how many days will 10 women working together finish it ?
Choose the correct choice from the following answers:
A) 50 days
B) 40 days
C) 60 days
D) 70 days
E) 90 days
Let 1 man's 1 day work = x   and 1 woman's 1 days work = y.   Then, 4x + 6y = 1/8   and 3x+7y = 1/10   solving, we get y = 1/400 [means work done by a woman in 1 day]   10 women 1 day work = 10/400 = 1/40   10 women will finish the work in 40 days   (40 days)
<result>B</result>
4 men&6women finish a job in 8days, while 3men&7women finish it in 10 days. In how many days will 10 women working together finish it ?