Correct Answer - Option 1 : 48 minutes

**Given: **

Walking at 4/5 of his usual speed, a man is 12 minutes late for his office

**Calculation**

Let the usual time be x minute

Walking at 4/5^{th} of his usual speed, he will take time 5/4 of the usual time

Now, 5/4^{th} of the usual time = usual time + 12 minute

5/4 x = x + 12

5/4x – x = 12

1/4 x = 12

X = 48 minute

Hence, he usually time take = 48 minute