Entrance Exams
Govt. Exams
A = P(1.1)^3 = 1.331P = 1331. P = 1000
Let price = 100. After -25% = 75. After +25% of 75 = 75 × 1.25 = 93.75. Net decrease = 6.25%
Net rate = 1/10 + 1/15 - 1/20 = (6+4-3)/60 = 7/60. Time = 60/7 ≈ 8.57. Rechecking: (6+4-3)/60 = 7/60, so 60/7. Let me verify: LCD(10,15,20)=60. 1/10=6/60, 1/15=4/60, 1/20=3/60. Net = 7/60. Time = 60/7 ≈ 8.57. But checking options, 9.6 = 48/5 = 9.6. Verifying: 7/60 gives 8.57, not 9.6. Re-examining: rates sum to 7/60, time = 60/7 ≠ options. This Q needs revision.
Increase = 300 - 250 = 50. Percentage = (50/250) × 100 = 20%
B's rate = 1/8 - 1/12 = (3-2)/24 = 1/24. B takes 24 days
Downstream speed = 120/4 = 30 km/h. Boat speed = 30 - 5 = 25 km/h
0.4 × x = 144. x = 144/0.4 = 360
C's CP = B's SP = 690. B's CP = 690/1.15 = 600. A's SP = B's CP = 600. A's CP = 600/1.2 = 500
A = P(1+r/100)^3. 9261 = 8000(1+r/100)^3. (1+r/100)^3 = 9261/8000 = 1.157625. 1+r/100 = 1.05. r = 5%
Total distance = 120 + 180 = 300m. Combined speed = 300/10 = 30 m/s = 30 × 3.6 = 108 km/h