(i) 20 minutes into seconds
20 minutes = 20 × 60 seconds = 1200 seconds
(ii) 5 hours 35 minutes 40 seconds into seconds
∴ 5 hours 35 minutes 40 seconds = 20,140 seconds
(iii) 3 1/2 hours into minutes
3 1/2 hours = 3 hours 30 minutes
= 3 × 60 minutes + 30 minutes
= 180 minutes + 30 minutes
= 210 minutes
∴ 3 1/2 hours = 210 minutes
(iv) 5580 minutes into hours
580 minutes = 580/60 hours = 9 hours 40 minutes
∴ 580 minutes = 9 hours 40 minutes
(v) 25200 seconds into hours
25200 seconds = 25200/60 minutes = 420 minutes
= 420/60 hours = 7 hours
∴ 25200 seconds = 7 hours
