Entrance Exams
Govt. Exams
Net rate = 1/10 + 1/15 - 1/12 = (6+4-5)/60 = 5/60 = 1/12. Time = 12 hours. [Recalculating: (6+4-5)/60 = 5/60 = 1/12, so time = 12 hours. Answer should be B, but let me verify: LCM(10,15,12)=60. 1/10+1/15-1/12 = 6/60+4/60-5/60 = 5/60 = 1/12. Time = 12 hours.]
SI = (P × R × T)/100 = (50000 × 12 × 3)/100 = Rs. 18000
Price after increase = 500 × 1.20 = 600. Final price = 600 × 0.90 = Rs. 540
Combined rate = 1/10 + 1/15 + 1/20 = 13/60. Work done in 2 days = 26/60. Remaining = 34/60. B+C rate = 1/15 + 1/20 = 7/60. Days = (34/60)/(7/60) = 34/7 ≈ 5.33 days
A's CP × 1.25 × 1.20 = 3000. A's CP × 1.5 = 3000. A's CP = Rs. 2000
12100 = 10000(1 + r/100)^2. (1 + r/100)^2 = 1.21. 1 + r/100 = 1.1. r = 10%
Upstream speed = 12 - 3 = 9 km/h. Time = 45/9 = 5 hours
Net rate = 1/8 - 1/12 = (3-2)/24 = 1/24. Time = 24 hours
Let original number = x. x × 1.20 = 480. x = 480/1.20 = 400
If boys:girls = 3:2 and boys = 15, then girls = (2/3) × 15 = 10