Time, Speed and Distance Questions

Multiple choice
  1. 4.25 h

  2. 5.15 h

  3. 5.75 h

  4. 6.15 h

  5. None of these

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

Rahul travels 50 km in the first hour, 45 km in the second, 40.5 km in the third, and 36.45 km in the fourth. Total distance covered in 4 hours is 171.95 km. The remaining 8.05 km is covered at a speed of 32.805 km/h, taking approximately 0.245 hours, totaling 4.245 hours.

Multiple choice
  1. 8 kmph

  2. 12 kmph

  3. 16 kmph

  4. 15 kmph

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

Let Britney's speed be v and Anna's be v-4. Britney travels 60 km and then returns 12 km, total 72 km. Anna travels 60 - 12 = 48 km. Since times are equal, 72/v = 48/(v-4). Solving gives 72v - 288 = 48v, so 24v = 288, v = 12.

Multiple choice
  1. 550 m

  2. 330 m

  3. 440 m

  4. 660 m

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

Relative speed = 90 + 108 = 198 kmph. Convert to m/s: 198 * (5/18) = 55 m/s. In 10 seconds, the distance covered is 55 * 10 = 550 m. This is the distance between them 10 seconds before they meet.

Multiple choice
  1. x - 6y = -12; 3x - 10y = -30

  2. 3x - 6y = 30; x - 10y = -12

  3. x - 3y = 12; x - 13y = 30

  4. x - 6y = -12; 3x - 10y = 30

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

Distance D = xy. (x+12)(y-2) = xy => xy - 2x + 12y - 24 = xy => -2x + 12y = 24 => x - 6y = -12. (x-10)(y+3) = xy => xy + 3x - 10y - 30 = xy => 3x - 10y = 30.

Multiple choice
  1. 4 miles

  2. 6 miles

  3. 8 miles

  4. 12 miles

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

Let d be the distance by bike. Then 33 - d is the distance by metro. Time by bike = d/6. Time by metro = (33 - d)/30. Given d/6 - (33 - d)/30 = 6/60 = 0.1. Multiply by 30: 5d - (33 - d) = 3. 6d = 36, so d = 6 miles.

Multiple choice
  1. 45

  2. 54

  3. 48

  4. 42

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

Let speed be v. 384/(v-16) - 384/v = 2. Solving for v: 384v - 384(v-16) = 2v(v-16). 384 * 16 = 2v^2 - 32v. v^2 - 16v - 3072 = 0. Roots are (16 +/- sqrt(256 + 12288))/2 = (16 +/- 112)/2. v = 64. 75% of 64 is 48.

Multiple choice
  1. 1 : 16, 3.75 km/hr

  2. 4 : 1, 15 km/hr

  3. 2 : 1, 30 km/hr

  4. 2 : 8, 240 km/hr

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

Distance D at speed s1 takes time t = D/s1. Half distance D/2 at speed s2 takes time 2t. So s2 = (D/2) / (2t) = D / (4t) = (D/t) / 4 = s1 / 4. Thus s1/s2 = 4/1. If s1 = 60, s2 = 15.