4 men and 6 women completes a work in 22 days. 7 men and 3 women working together will complete the whole work in how many days, if efficiency of a man is 25% less than that of women ? 4 पुरूष तथा 6 महिलाएँ किसी कार्य को 22 दिनों में समाप्त करते हैं। 7 पुरूष तथा 3 महिलाएँ एक साथ कार्य करते हुए कितने दिनों में कार्य समाप्त करेंगे यदि एक पुरूष की क्षमता महिला की क्षमता से 25% कम है ?

Let a woman's efficiency = 1 unit/day. Then a man's efficiency = 0.75 units/day (25% less). 4 men + 6 women in 22 days: Total work = 22(4 × 0.75 + 6 × 1) = 22(3 + 6) = 22 × 9 = 198 units. 7 men + 3 women: Combined efficiency = 7 × 0.75 + 3 × 1 = 5.25 + 3 = 8.25 units/day. Days needed = 198/8.25 = 24 days. The key insight is that men are less efficient than women (75%), so we use 0.75 for men.