Explanation

 1 hour = 820 jumps

30 minutes = (820 ÷ 2) = 410 jumps

Explanation

Batman current runs rate

= 100/38

=2.63

Runs in 47.5 overs

=47.5x2.63

=124.925 (125)

Explanation

Work done by 8 men or 12 women in 25 days:

Work done by 8 men in 25 days = 1 complete piece of work.

Work done by 12 women in 25 days = 1 complete piece of work.

Explanation

Let:

• M1 = Number of machines in the first case = 8
• D1 = Number of days taken in the first case = 10
• M2 = Number of machines in the second case = 16
• D2 = Number of days taken in the second case =?

The formula for inverse proportion is: M1 * D1 = M2 * D2

Substitute the values: 8 * 10 = 16 * D2 80 = 16 * D2

To find D2, divide both sides by 16: D2 = 80 / 16 D2 = 5

So, it will take 16 machines 5 days to do the work.

Explanation

When the trains move in opposite directions, their relative speed is the sum of their individual speeds:

60 km/h + 40 km/h = 100 km/h

To convert this to meters per second, divide by 3600 (since there are 3600 seconds in an hour):

100 km/h ÷ 3600 = 27.78 m/s (approximately)

The total distance covered by the trains as they cross each other is the sum of their lengths:

140 m + 160 m = 300 m

Time = Distance ÷ Relative Speed

Time = 300 m ÷ 27.78 m/s ≈ 10.8 s

Explanation

Explanation

 To calculate the duration between 21:30 (9:30 PM) and 7:30 (7:30 AM), follow these steps:

Convert to 24-Hour Format:

Departure: 21:30

Arrival: 07:30 (next day)

Calculate Duration:

From 21:30 to midnight (00:00): 2 hours 30 minutes

From midnight to 07:30: 7 hours 30 minutes

Total duration: 2:30 + 7:30 = 10 hours

Therefore, the correct answer is B. 10 Hours.

Explanation

Car A:

• Time = 3 hours 20 minutes = $3 + frac{20}{60} = 3.33$ hours

• Distance = 300 km

Car B:

• Time = 2 hours 80 minutes = 2+80/60​=3.33 hours

• Distance = 280 km

Total Distance

$$300 , text{km} + 280 , text{km} = 580 , text{km}$$

Total Time

$$3.33 + 3.33 = 6.66 , text{hours}$$

Average Speed Formula:

$$text{Average speed} = frac{text{Total Distance}}{text{Total Time}} = frac{580}{6.66} approx 87.09 , text{km/h}$$Total Time=580/ 6.66​≈87.09km/h

$$$$
boxed{87.1 , text{km/h (approx)}}

Explanation

Explanation

Total distance:

• Length of the train: 99m
• Length of the station: 231m
• Total distance = Length of the train + Length of the station = 99m + 231m = 330m

Total time: 11 seconds

Speed:

• Speed = Distance / Time
• Speed = 330m / 11s = 30 m/s

Now, we need to convert m/s to km/h:

• 1 m/s = 3.6 km/h

So, 30 m/s = 30 * 3.6 = 108 km/h

Therefore, the speed of the train is 108 km/h.