NCERT Solutions for Class 4 Mathematics Unit-4 Tick-Tick-Tick
NCERT Textbook Page 36
Practice Time
1. Three friends read time from a clock. Who is right?
Ans. In the first clock, short hand or hour hand is pointing to 3 and long hand or minute hand is pointing to 12. Hence, the time is 3:00.
It means Pinki is right.
In the second clock, Pinki is right. The clock is showing the time 5:35.
In the third clock also Pinki is right. The clock is showing the time 7:15.
NCERT Textbook Page 37
1. Show the following times in the clock.
Ans. The time showing figures of watches are being given here.
2. Do you like sky watching? If yes, then this one should interest you.
(a) At what time does the sun rise at your place?
Ans.
(b) When does the sun set?
Ans.
(c) Does the sun rise and set at the same times every day?
Ans. No.
(d) Look at the newspaper and see the time of sunrise and sunset in different months.
Ans. The sunrise and sunset time is given in the table in New Delhi for the 1st date of different month in a year.
NCERT Textbook Page 38
Find Out
1. How long will it take the minute hand to move from
Ans.
NCERT Textbook Page 39
1. Draw where the hands will be
Ans.
2. How long does your school assembly take?_______
Ans. My school assembly takes 15 minutes.
3. How long is your lunch break?
Ans. The lunch break in my school is 30 minutes long.
4. How long is your games period?
Ans. The games period is 45 minutes long in my school.
5. Is it the same as all the other periods?
Ans. Yes, all other periods take same length of time.
6. The games period and lunch break seem very short! Aren’t they?
Ans. No, these are of enough length.
NCERT Textbook Page 40
1. How many minutes can these activities take? Make a guess and then check at home.
• Boiling of 1 litre of milk.
Ans. It takes about 5 minutes.
• Filling a bucket.
Ans. It takes about 2 minutes.
• Sweeping your room.
Ans. It takes about 3 minutes.
Activity Time
1. In one’minute, how many times can you________
(a) Snap your finger _______________
(b) Skip a rope _______________
(c) Jump up and down _______________
(d)_______________ _______________
Write more such fun activities in this column.
Ans.
(a) Snap your finger 15 times
(b) Skip a rope 30 times
(c) Jump up and down 40 times
(d) Blinking of eyelids 100 times
2. Here is another challenge for you. How long can you_________
(a) Speak non-stop ________________
(b) Stand on one leg ________________
(c) Sing ‘Aaaaa..without a break ________________
Ans.
(a) Speak non-stop 4 minutes
(b) Stand on one leg 1 minute
(c) Sing‘Aaaaa…’without a break 1 minute
3. How long do you take to________
(a) Run a 50 metre race _______________
(b) Collect 50 pebbles from the ground _______________
(c) Count 1 to 100 _______________
Ans.
(a) Run a 50 metre race 3 minutes
(b) Collect 50 pebbles from the ground 2 minutes
(c) Count 1 to 100 1 minute
NCERT Textbook Page 41
1. Let’s look at a clock again! Solve this one
(a) The minute hand started from ‘2’. How many minutes will it take to come back to ‘2’ again?
Ans. It takes 60 minutes. As it makes one rotation in 60 minutes.
(b) What happens to the hour hand? Does it also move? How long will it take to move from one number to the next?
Ans. Hour hand shows hour in watch. So it takes one hour to move from one number to the next one.
(c) Look around you and list the activities that take about one hour to complete.
1.____________ 2.____________
3.____________ 4.____________
5.____________
Ans. List of some common activities which take about one hour to complete.
1. Going to the temple and coming back.
2. Cleaning of house.
3. Completing one small chapter of math.
4. Preparing of breakfast by my mother.
5. Drawing a picture in my drawing book.
2. How long does it take to cook dinner at home? More than an hour/less than an hour.
Ans. It takes a bit more than an hour.
3. Ask your father if he can cook as fast as your mother does. Yes/No.
Ans. No.
4. Which games take less than an hour to finish?
Ans. Some games such as race, high jump, long jump, relay race, swimming, etc. take less than an hour to finish.
5. How long does a football match take?
Ans. The duration of a standard adult football match is 90 minutes plus 15 minutes break.
NCERT Textbook Page 43 .
Rani’s Diary
1. Mark these in the correct order on Muniya’s Time Line.
Ans. The correct order on Muniya’s Time Line
2. Muniya got her first tooth in September. How many months old was she then? How many months have passed from March to September?
Ans. She was about 6 months old when she got her first tooth. Seven months have passed from March to September.
3. How old was Muniya, when
(a) She first sat up? (b) She got her first tooth?
Ans. (a) Muniya was eight months old when she sat up first.
(b) Muniya was about six months old when she got her first tooth.
4. What did she do first
(a) Walking/eating a banana? (b) Crawling/standing?
Ans. (a) First she ate banana. (b) First she started crawling.
NCERT Textbook Page 44
1. Now make a time-line of a dog’s life in your notebook.
Ans. Time line of a dog’s life is given here:
2. Note the differences between Muniya and Rani’s puppy.
Ans. Differences between Muniya and Rani’s puppy
NCERT Textbook Page 45
Find Out
1. Do all animals grow at the same speed?
Ans. No, all animals do not grow at the same speed.
2. Find about the growth of:
(a) A hen (b) A cow (c) A bird
Ans. These animals grow in the following order:
A bird, A hen, A cow.
3. Draw pictures of the baby animals and the big animals.
Ans.
4. Here are the pictures of grandfathers posing for a photograph. Who looks the oldest to you?
Ans. Rani’s grandfather
• How much older is Appu’s grandfather than Rani’s grandfather?
Ans. Age of elephant Appu’s grandfather = 95 years
Age of Rani’s grandfather = 70 years.
So, Appu’s grandfather is (95-70) 25 years older than Rani’s grandfather.
• Will Chuchoo’s grandfather ever grow as old as Appu’s grandfather?
Ans. Never.
• How much younger is Chuchoo rat’s grandfather than Rani’s grandfather?
Ans. Age of Rani’s grandfather = 70 years
Age of Rat’s grandfather = 2 years Difference = 70 – 2 = 68 years
Hence, Chuchoo rat’s grandfather is 68 years younger than Rani’s grandfather.
NCERT Textbook Page 47
Holidays are Fun
1. Now write which dates these stand for
5/5/06__________ 20/5/06__________
7/6/06 __________ 1/1/07__________
Ans.
5/5/06 5 May 2006 20/5/06 20 May 2006
7/6/06 7 June 2006 1/1/07 1 January 2007
2. Write these dates in numbers.
1 June 2006 ________
30 May 2006 ________
10 August 2007 ________
Ans.
1 June 2006 1/6/06
30 May 2006 30/5/06
10 August 2007 10/8/07
3. How long did it take the letter to reach from Ajmer to Nagpur?
Ans. Atif wrote letter on 1/5/06 from Ajmer. Shobhna got this letter on 6/5/06 in Nagpur. Therefore, it took 5 days to reach from Ajmer to Nagpur.
4. How many days will Atif spend at his Nani’s place?
Ans. Atif went to his Nani’s place on 5/5/06 and returned back on 20/5/06 So, he spent (20 – 5) = 15 days at his Nani’s place.
5. Fill in the table
Ans.
6. Who has got longer holidays—Shabana or Atif?
Ans. Shabana’s school was closed for 70 days while Atifs school was closed for 60 days.
Therefore, Shabana got longer holidays.
7. Which long holidays do you get in school? Fill the table.
Calculation of number of days during these holidays Summer holidays
From 1st June to 30 June = 30 days (30 -1 + 1)
From 1st July to 2nd July = 2 days
Total = 30 + 2 = 32 days
Autumn Break
From 12 October to 19 October
= 8 days (12, 13,14, 15, 16, 17, 18, 19 = total 8 days)
Winter Break
From 25 December to 31st December
= (25, 26, 27, 28, 29, 30, 31) = 7 days
From 1st January to 5th January
= (1.2, 3, 4, 5) = 5 days
Total = 7 + 5 = 12 days
Holidays after exam
From 5th March to 31st March = 27 days
From 1st April to 1st April = 1 day
Total = 27+1=28 days
NCERT Textbook Page 48
1. On 15 May 2006 Chandran went to a shop to buy butter. He checked the packet to see if this butter was safe to eat.
It was written on the packet-Best before 180 days from the date of packing. Then he checked the date of packing. It was 15/01/06. Help him find out if he should buy this butter or not.
• In which month was the butter packed?
Ans. The butter was packed in the month of January. It was on 15th January 2006.
• Which month will it be 180 days after 15/01/06?
Ans. We will calculate the days from 16/01/2006
From 16th January 2006 to 31st January 2006 = 16 days
From 1st February 2006 to 28th February 2006 = 28 days
From 1st March 2006 to 31st March 2006 = 31 days
From 1st April 2006 to 30th April 2006 = 30 days
From 1st May 2006 to 31st May 2006 = 31 days
From 1st June 2006 to 30th June 2006 = 30 days
Total = 166 days
Now, 180 – 166 = 14 days left to be completed in 180 days So, 14 days will be completed on 14th August 2006.
Hence, in the month of August on 14th, the 180 days will be completed after manufacturing date.
• Can Chandran eat it on 15th May 2006?
Ans. Yes, because 15th May 2006 falls before 14th August 2006.
2. Do you ever check the date of packing of things you buy?
Ans. Yes, I checked the date of packing of things before bought it.
3. Have you seen medicines which have the expiry date written on them? It tells you after which date it is unsafe to take the medicine.
Ans. Yes, I saw medicines which have the expiry date written on them. It is safe to take those medicines before expiry date.
Find Out
4. Which are the other things that come with an expiry date?
On a cough syrup it was written:
Mfg. date 07/03
This shows it was made in July 2003.
Exp. date 07/05
This shows the month and year till when it is safe to take.
Ans. Expiry date is written on all medicines.
On a cough syrup, it was written Mfg. date-07/03, and Exp. date-07/05, this means this was manufactured in July 2003 and expired on July 2005. So, it is safe to take this medicine before July 2005.
5. What month and year is written as 07/05?
Ans. This stands for July 2005.
6. Would it be safe to take the cough syrup in September 2005?
Ans. As we saw this is the expiry date written oi} the cough syrup in the example given above, so it is not safe to take this medicine in September 2005.
NCERT Textbook Page 49
1. Can you guess why they missed the train?
Ans. Railway uses 24 hours clock time. And their ticket shows 5:30 means the train
was in the morning and they reached the station in the 5:15 evening, so they l missed the train.
NCERT Textbook Page 50
1. Look at this chart. It tells the difference between your watch and a 24 hour clock. Try to complete it.
Ans.
NCERT Textbook Page 51
1. Now can you tell why a 24-hour clock is called so?
Ans. A 24-hours clock show the time for whole day which is of 24 hours. Hence, it is called so.
2. Suppose a train leaves at 8:30 at night. The time written on the Railway ticket would be________
Ans. The time for 8:30 night would be written on a railway ticket as 20:30.
3. You must have noted the time of sunrise and sunset. Write here using am and pm.
Ans. The time for sunrise and sunset on the 1st March
4. Where have you seen a 24-hour clock being used?
1._______________ 2.______________ 3._______________
Ans.
1. In airport timetable 2. In railways time table 3. In bus time table.
