Govt Exams
Number = 45 × 100/15 = 300. 40% of 300 = 300 × 40/100 = 120
Work done in 3 days = 3(1/12 + 1/18) = 3(3/36 + 2/36) = 3 × 5/36 = 5/12. Remaining = 7/12. Y completes 7/12 in (7/12)/(1/18) = 7/12 × 18 = 10.5 days
P(1.2)² = 14400. P × 1.44 = 14400. P = Rs. 10000
Downstream speed = 72/3 = 24 km/h. Upstream speed = 72/6 = 12 km/h. Current = (24-12)/2 = 6 km/h
Net rate = 1/20 + 1/30 - 1/40 = 6/120 + 4/120 - 3/120 = 7/120. Time = 120/7 ≈ 17.14 minutes
Marked Price = 8000 × 150/100 = 12000. Selling Price = 12000 × 90/100 = 10800. Profit = 10800 - 8000 = Rs. 1600
Net rate = 1/15 - 1/20 = 4/60 - 3/60 = 1/60. Time = 60 hours
CP = 1200 × 100/120 = Rs. 1000
Total distance = 180 + 220 = 400m. Relative speed = 400/9 m/s = 160 km/h. Speed of second train = 160 - 40 = 32 km/h
Combined rate = 1/6 + 1/8 + 1/12 = 4/24 + 3/24 + 2/24 = 9/24