What is the average speed of a train that covers 80km in 1hours, 200km in 2hours, and 420km in 4 hours

The average speed of the train is 100 km/hr

Speed refers to the rate of change in distance.

It is calculated by dividing distance by time taken.

Average speed is calculated by dividing the total distance covered and the total time taken.

In this case;

Total distance covered by the train  = 80 km + 200 Km + 420 km

                       = 700 km

Total time taken = 1 hr + 2 hrs + 4 hrs

                            = 7 hrs

Therefore;

Average speed = 700 km ÷ 7 hrs

                         = 100 km/hr

Thus, the average speed of the train is 100 km/hr

The average speed of the train that covers 80 km in 1 hour, 200 km in 2 hours, and 420 km in 4 hours is 100 Km/h

Average speed is defined as the total distance travelled divided by the total time taken. Mathematically, it is expressed as:

With the above formula, we can obtain the average speed of the train as illustrated below:

Total distance = 80 + 200 + 420 = 700 Km

Total time = 1 + 2 + 4 = 7 hours

Therefore, the average speed of the train is 100 Km/h

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1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%

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