NCERT Solutions for Class 4th Maths Chapter 12 Hours and minutes — Let Us Do
Book page 181 – 182 Updated on2026-09-19
Q1.
Show the appropriate times on the clock as per instructions. a) Raghav started doing his homework at 10:20 AM. He took 25 minutes to finish it. Show the time that he finished his homework.
Answer
Started at 10:20 AM
Time after 25 minutes
The clock printed in the book shows the starting time. The second clock is empty for you to fill.
Add the 25 minutes to the minutes he started with.
20 + 25 = 45 45 is less than 60, so the hour stays 10 He finished at 10:45 AM
Finished at 10:45 AM
The finishing time. Blue hand = hour, red hand = minutes.
To show it: put the long hand on 9 (because 9 × 5 = 45 minutes) and the short hand between 10 and 11, closer to 11.
Why it happens: Minutes only turn into a new hour when they reach 60. Here 45 is still under 60, so the hour number does not change.
Q2.
b) Muneera starts reading a story at 4:15 PM. She finishes reading it in 45 minutes. Show the time that she finished reading the story.
Answer
Started at 4:15 PM
Time after 45 minutes
The clock printed in the book shows the starting time. The second clock is empty for you to fill.
Add the 45 minutes to the minutes she started with.
The finishing time. Blue hand = hour, red hand = minutes.
To show it: put the long hand on 12 and the short hand exactly on 5.
Why it happens: The minutes added up to a full 60, which is one whole hour, so the hour hand moves on to the next number and the minutes start again from 0.
Tip: 45 minutes is three quarters of an hour, and 15 minutes is one quarter. Three quarters and one quarter make one whole hour.
Q3.
c) Akira leaves for school at 8:00 AM. She reaches school in 15 minutes. Starts for school at 8:00 AM → Reaches school at ______AM → Finishes school assembly ______AM → Dance practice ends at ______AM → Break ends at ______AM (Time after 15 minutes, time after 15 minutes, time after 20 minutes, time after 10 minutes)
Answer
Starts for school at 8:00 AM
Reaches school at ______AM
Finishes school assembly ______AM
Dance practice ends at ______AM
Break ends at ______AM
Akira’s morning. The arrows above say: time after 15 minutes, time after 15 minutes, time after 20 minutes, time after 10 minutes.
Add the minutes one step at a time.
8:00 + 15 min → 0 + 15 = 15 → 8:15 AM (reaches school) 8:15 + 15 min → 15 + 15 = 30 → 8:30 AM (assembly ends) 8:30 + 20 min → 30 + 20 = 50 → 8:50 AM (dance practice ends) 8:50 + 10 min → 50 + 10 = 60 = 1 hour → 9:00 AM (break ends)
8:00 AM
+15 min → 8:15 AM
+15 min → 8:30 AM
+20 min → 8:50 AM
+10 min → 9:00 AM
The whole chain filled in. Blue hand = hour, red hand = minutes.
Blank
Time
Reaches school at
8:15 AM
Finishes school assembly
8:30 AM
Dance practice ends at
8:50 AM
Break ends at
9:00 AM
Check it yourself: Add all the minutes together: 15 + 15 + 20 + 10 = 60 minutes. That is exactly 1 hour, so Akira ends at 9:00 AM, one hour after 8:00 AM.
Why it happens: Whenever the minutes reach 60 they become one full hour, so 8:50 + 10 minutes is written as 9:00 and not as 8:60.