Correct Answer - Option 2 : 4 km

**Given:**

Distance = Speed × Time

**Calculation:**

Let the distance from house to school be **d km **and original speed be **s km/hr**

Original time taken to reach school = Distance/Speed = d/s

Now, A/Q

d/s - d/4 = 10/60 ----(1)

d/3 - d/s = 10/60 ----(2)

Adding eq (1) and eq (2)

(d/3) - (d/4) = (1/6) + (1/6)

⇒ d/12 = 1/3

⇒ d = 4 km

**∴ The distance from house to school is 4 km**