Question

One man, 3 women and 4 boy can do a piece of work in 96 hours, 2 men and 8 boys can do it in 80 hours, 2 men and 3 women can do it in 120 Hours, then 5 men and 12 boys can do it in ??
please anyone provide me direct formula or any short tricks for this math .​

Answer 1

let no. of hours taken by 5 men and 12 boys be x

total no. of people in 4th case= 5+12

=17

no. of people in 3rd case = 2+3

=5

no. of people(p) 5 , 17

no. of hours(q) 120 , x

more the no. of people, less the time taken, hence P and q vary inversely

p×q=5×120=17×x

600=17x

600/17=x

35.29=x