Time, Speed and Distance Questions

Multiple choice
  1. 1H 45 min

  2. 2H 25 min

  3. 1H 15 min

  4. 2 H 45 min

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

Upstream speed = 55 km / (2h 45m) = 55/2.75 = 20 kmph. Stream speed = 32 - 20 = 12 kmph. Downstream speed = 32 + 12 = 44 kmph. Time downstream = 55/44 = 1.25 hours = 1 hour 15 minutes. The relationship between still water speed, stream speed and direction is key.

Multiple choice
  1. 4 hour 44 min

  2. 5 hour 45 min

  3. 6 hour 30 min

  4. 7 hour 54 min

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

Speed = 250 m/min = 0.25 km/min. Distance = 96 km. For every 6 km: cycling time = 6/0.25 = 24 min, plus 6 min rest = 30 min per segment. Number of segments = 96/6 = 16. Total cycling time = 16 × 24 = 384 min. Rest periods = 15 intervals × 6 = 90 min. Total time = 384 + 90 = 474 min = 7 hours 54 minutes.

Multiple choice
  1. 4.2 km/hr

  2. 3.6 km/hr

  3. 4.8 km/hr

  4. 3.2 km/hr

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

Speed against stream = 0.72 km / 0.2 h = 3.6 km/h. Speed with stream = 0.72 km / 0.15 h = 4.8 km/h. If v is speed in still water and u is stream speed, then v - u = 3.6 and v + u = 4.8. Solving: v = (3.6 + 4.8)/2 = 4.2 km/h.

Multiple choice
  1. 400

  2. 720

  3. 180

  4. 360

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

Let distance be d km. Time going = d/45 hours. Time returning = d/40 hours. We know returning takes 1 hour longer: d/40 = d/45 + 1. Solving: Multiply by 360: 9d = 8d + 360, so d = 360 km. This is a classic time-speed-distance problem where the difference in time gives us the equation.

Multiple choice
  1. 0.4

  2. 0.2

  3. 1

  4. 0.6

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

Let swimmer's speed in still water be v m/s and current speed be s m/s. Against current for 6 min (360 sec): distance = (v - s) × 360. With current for 6 min (360 sec): distance = (v + s) × 360. Net displacement between P and Q = distance with current - distance against current = [(v + s) - (v - s)] × 360 = 2s × 360 = 720s meters. Given net displacement is 120 m, so 720s = 120, s = 120/720 = 1/6 m/s = (1/6) × (3600/1000) km/h = 0.6 km/h.

Multiple choice
  1. 28 km/h

  2. 25 km/h

  3. 20 km/h

  4. 24 km/h

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

Let original speed be x km/h. Distance = 80 km. Normal time = 80/x hours. New speed = (x+4) km/h. New time = 80/(x+4) hours. Since new time is 1 hour less: 80/x - 80/(x+4) = 1. Solving: 80(x+4) - 80x = x(x+4), 320 = x² + 4x, x² + 4x - 320 = 0, (x+20)(x-16) = 0, x = 16 km/h. Changed speed = 16+4 = 20 km/h.

Multiple choice
  1. 6.75 km

  2. 5.55 km

  3. 3.25 km

  4. 4.20 km

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

Speed of boat in still water = 6 km/h, speed of stream = 3 km/h. Downstream speed = 6 + 3 = 9 km/h. Upstream speed = 6 - 3 = 3 km/h. Total time = 3 hours. Let distance = d km. Time downstream + Time upstream = d/9 + d/3 = d/9 + 3d/9 = 4d/9 = 3. Solving: 4d = 27, d = 6.75 km.

Multiple choice
  1. 200m

  2. 180m

  3. 150m

  4. 250m

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

Relative speed = 15 - 5 = 10 m/s. Initial gap = 500 m. Time to catch = 500 ÷ 10 = 50 seconds. In 50 seconds, chain snatcher covers 5 × 50 = 250 m. Verification: Policeman covers 15 × 50 = 750 m, gap closed = 750 - 250 = 500 m ✓. Option D is correct.

Multiple choice
  1. 6 km/hr

  2. 4 km/hr

  3. 5 km/hr

  4. 7 km/hr

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

When speed increases to 6/5 of actual speed, time decreases to 5/6 of actual time (inverse proportion). The time saved is 1 hour, which is 1 - 5/6 = 1/6 of actual time. So actual time = 6 hours. With distance 30 km and time 6 hours, actual speed = 30/6 = 5 km/hr. At 6/5 speed (6 km/hr), time = 30/6 = 5 hours, saving 1 hour as given.

Multiple choice
  1. $25 : 16$
  2. $5 : 16$
  3. $36 : 25$
  4. $31 : 19$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Train from H runs for 5 hours (6:30pm to 11:30pm) at 90 km/hr = 450 km. Train from K runs for 4 hours (7:30pm to 11:30pm) at 72 km/hr = 288 km. Ratio HJ:KJ = 450:288 = 25:16 after dividing by 18. Option B reverses the ratio. Options C and D don't match the calculation.

Multiple choice
  1. 75 km

  2. 55 km

  3. 60 km

  4. 80 km

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

Let distance = d km. Time going = d/60 hours, time returning = d/30 hours. Since return took 1 hour longer: d/30 - d/60 = 1. Solving: (2d-d)/60 = 1, so d/60 = 1, giving d = 60 km. The key insight is that slower speed (30 km/hr vs 60 km/hr) means more time for the same distance.

Multiple choice
  1. 2 km/hr. 2 किमी./घंटा

  2. 6 km/hr. 6 किमी./घंटा

  3. 8 km/hr. 8 किमी./घंटा

  4. 10 km/hr. 10 किमी./घंटा

  5. 12 km/hr. 12 किमी./घंटा

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

Downstream speed: 30/2.5 = 12 km/hr. Upstream speed: 30/3.75 = 8 km/hr. Still water speed = (downstream + upstream)/2 = (12 + 8)/2 = 10 km/hr. This formula works because downstream = boat + stream, upstream = boat - stream.

Multiple choice
  1. 30 km 30 किमी

  2. 35 km 35 किमी

  3. 42 km 42 किमी

  4. 25 km 25 किमी

  5. None of these इनमें से कोई नहीं

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

Let one-way distance = d km. Time by train = d/35 hr, walking back = d/6 hr. Total time = 8hr 12min = 8.2hr = 41/5 hr. So d/35 + d/6 = 41/5. Common denominator 210: 6d + 35d = 41 × 42. 41d = 1722, so d = 42 km.