Time, Speed and Distance Questions

Multiple choice
  1. Only (i)

  2. Only (i) and (ii)

  3. Only (iii) and (ii)

  4. All (i), (ii), (iii) and (iv)

  5. Only (i), (ii) and (iv)

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The distance AB is 6 * 20 = 120 km. Let boat speed be u, stream speed v. 120/(u+v) + 120/(u-v) = 15. With 2v: 120/(u+2v) + 120/(u-2v) = 24. These equations allow solving for u and v, and subsequently answering all parts.

Multiple choice
  1. Quantity 1 > Quantity 2

  2. Quantity 1 ≥ Quantity 2

  3. Quantity 2 > Quantity 1

  4. Quantity 2 ≥ Quantity 1

  5. Quantity 1 = Quantity 2 or relation cannot be established

Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice
  1. Only I & II

  2. Only I & III

  3. All I, II & III

  4. Any two of them

  5. None of these

Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Let still water speed = x, current speed = c. Upstream: (x-c)×4 = y. We need x. Statement I: c=1.5, but y unknown. Statement II: (x+c)×5=60, but c unknown. Statement III: (x+c)×3=y, relates y and x+c. No single pair suffices - you need all three to solve. Any two statements leave too many unknowns.

Multiple choice
  1. 3.5 km.

  2. 4.5 km.

  3. 5.5 km.

  4. 6.5 km.

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let distance up the hill be d km. Time up = d/2.5 hours, time down = d/3.25 hours. Total time = d/2.5 + d/3.25 = 4 hours 36 minutes = 4.6 hours. Multiplying by 325: 130d + 100d = 1494.5, so 230d = 1494.5, giving d = 6.5 km. Verification: 6.5/2.5 = 2.6 hr up, 6.5/3.25 = 2 hr down, total = 4.6 hr = 4hr 36min.

Multiple choice
  1. 2.75 km.

  2. 3.75 km.

  3. 7.5 km.

  4. 9 km.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Let distance = d km. A's time = d/10 + d/9 = (9d+10d)/90 = 19d/90 hours. B's time = 2d/12 = d/6 hours. B took 10 minutes less: d/6 - 19d/90 = 10/60. Converting: (15d-19d)/90 = 1/6, so -4d/90 = 1/6. This gives d = -90/24 = -3.75, but taking absolute value and reconsidering the equation setup: Actually A took MORE time, so 19d/90 - d/6 = 1/6, giving 4d/90 = 15/90, so d = 15/4 = 3.75 km.

Multiple choice
  1. 86 km.

  2. 72 km.

  3. 94 km.

  4. 96 km.

  5. None of these

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Father's time = d/16 hours. Son starts 60 min (1 hour) later, so son's travel time = d/24 hours. Son reaches 60 min (1 hour) before father. So: d/16 = d/24 + 1 + 1 = d/24 + 2. Multiply by 48: 3d = 2d + 96, so d = 96 km. Option D is correct.

Multiple choice
  1. 1 : 4

  2. 4 : 1

  3. 1 : 2

  4. 2 : 1

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Let the cyclist's speed be v and time be t, so distance d = vt. The jogger covers d/2 distance in 2t time, so jogger's speed = (d/2)/(2t) = d/4t = v/4. Therefore, jogger's speed : cyclist's speed = v/4 : v = 1 : 4.

Multiple choice
  1. 1:20 am

  2. 12 pm

  3. 6 pm

  4. 11 pm

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Total time needed = distance/speed = 999/55.5 = 18 hours. With a stop of 1 hour 20 minutes, total journey time = 18 hours + 1 hour 20 minutes = 19 hours 20 minutes. Starting from 6 am, adding 19 hours 20 minutes gives 1:20 am the next day.

Multiple choice
  1. 15 km/hr

  2. 20 km/hr

  3. 25 km/hr

  4. 30 km/hr

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let downstream speed = (d+6) km/hr and upstream speed = (d-6) km/hr where d is speed in still water. Distance is same: 12(d+6) = 18(d-6). Solving: 12d+72 = 18d-108, so 6d = 180 and d = 30 km/hr. The distance cancels out when equating both expressions.

Multiple choice
  1. 3:2

  2. 5:3

  3. 4:5

  4. 3:5

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When two people start from opposite ends and meet, the ratio of their speeds equals the ratio of distances covered. John covers 75 km and Vinod covers 125-75 = 50 km when they meet. Therefore, the ratio of John's speed to Vinod's speed = 75:50 = 3:2. This is because they travel for the same duration until meeting, so speed ratio directly equals distance ratio.

Multiple choice
  1. 2 km./hr.

  2. 1.5 km./hr.

  3. 2.5 km./hr.

  4. 1.8 km./hr.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Downstream speed = 28/5 = 5.6 km/h. Upstream speed = 13/5 = 2.6 km/h. Stream speed = (downstream - upstream)/2 = (5.6 - 2.6)/2 = 3/2 = 1.5 km/h. This is a standard formula: speed of current = (speed with stream - speed against stream) / 2.

Multiple choice
  1. 80 km.

  2. 40 km.

  3. 70 km.

  4. 30 km.

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let distance = d km. At 40 km/h: time = d/40 hours. At 35 km/h: time = d/35 hours. Difference = 15 min = 0.25 hours. So d/35 - d/40 = 0.25. Solving: d(1/35 - 1/40) = 0.25 → d(5/1400) = 0.25 → d = 0.25 × 280 = 70 km. At 70 km, time at 40 km/h = 1.75 hr; at 35 km/h = 2 hr (15 min late).