36 Men completes a work in 24 days working 8 hour daily. 48 women completes same work in 20 days working 10 hours daily. 12 men and 24 women together working 12 hours/day will complete total work in how many days?(approx)

Men's work: 36 men × 24 days × 8 hours = 6912 man-hours. Women's work: 48 women × 20 days × 10 hours = 9600 woman-hours. These equal same work, so 1 woman = 6912/9600 = 0.72 men. New team: 12 men + 24 women = 12 + 24×0.72 = 12 + 17.28 = 29.28 men equivalent. Time = 6912/(29.28 × 12) = 6912/351.36 ≈ 19.67 days ≈ 19.7 days.