In how many days 6 girls and 4 boys together can

Solution

From (A), 18 girls can do the work in 10 days. So, 6 girls can do it in [if gte msEquation 12]> 18 ×10 6 [if !msEquation]-->[endif]--> `(18 x 10)/(6)` = 30 days. From (B), 10 boys can complete tree-fourth of the work in 6 days. Therefore, 10 boys can do the entire work in 6 x `(4)/(3)` = 8 days. So, 4 boys can do it in `(10 x 8)/(4)` [if gte msEquation 12]> 10 ×8 4 [if !msEquation]-->[endif]--> = 20 days. By combining (i) and (ii): Required no. of days = `(30 x 20)/(50)` [if gte msEquation 12]> 30 ×20 50 [if !msEquation]-->[endif]--> = 12 days C. (72G + 48 B) =1 12(6G + 4 B) = 1 6g + 4 B = 12 days Hence, either A and B together or C alone is sufficient to answer the question.