Page 7 - PPT 7

We know that, 60 minutes = 1 hour

Now, 140 minutes = 120 minutes + 20 minutes

= 60 minutes + 60 minutes + 20 minutes

= 60 minutes + 80 minutes

= 1 hour + 80 minutes

= 1 hour 80 minutes

Step 3: The LHS can now be written as

4 hours 140 minutes = 4 hours + 140 minutes

= 4 hours + 1 hour + 80 minutes

= 5 hours + 80 minutes

= 5 hours 80 minutes

Therefore, the required answer is 5.