Question

if 2 men and 3 boys can do a work in 10 days while 3 men and 2 boys came do the work in 7 days how long will 5 men and 4 boys take to do it​

Answer 1

Use the equations,

$2m \: + \: 3b \: = \frac{1}{10}$

$3m \: + \: 2b \: = \: \frac{1}{7}$

Equate and find the value of 5m + 4b.