Answer:
Distance between hometown and school is 318.6 km
Explanation:
Initially, the driving speed is 100 km/hr and the distance covered having this speed is 180 km.
The time taken to cover this distance is determine by the relation:
[tex]t=\frac{s_{1}}{u }[/tex]
Here u is initial speed and s₁ is the distance covered.
Substitute 100 km/hr for u and 180 km for s₁ in the above equation.
[tex]t=\frac{180}{100}[/tex]
t = 1.8 hr
Now, the speed is decreased to 63 km/hr due to rain.
Total time taken to reach home from school is 4 hours. But. 1.8 hrs is used to covered 180 km, so the remaining time is left to traveled the remaining distance to reach home.
Remaining time, t₁ = (4 - 1.8)hr = 2.2 hr
Distance covered in time 2.2 hr having speed 63 km/hr is:
s₂ = 63 x 2.2 = 138.6 km
The total distance between hometown and school is:
s = s₁ + s₂ = 180 + 138.6
s = 318.6 km
