NCERT Solutions for Class 3 Mathematics Chapter-7 Time Goes On
Ulta Pulta Time
1.This is a story with topsy turvy time.
As the sun sets———Sumana wakes up. What a lovely evening!———. She washes her face fast in 2 hours———and runs out. She goes straight to the bird’s nest. She has been watching the eggs for the last few months———.She was waiting for the baby birds to come out. But before she can blink her eyes, in a week———a cat jumps on to the tree. The mother bird cries loudly and Sumana rushes to shoo away the cat. As the cat jumps, it hits the big green mango. Dhum!
In two days———it is on the ground! Oh, how sad! The mango is still not fully ripe. It needed one more year——— to become sweet. Suddenly Sumana’s sister calls but—Are you still not hungry? Has your stomach clock gone to sleep? Come and eat hot upma for dinner——— .
Wasn’t that funny? You must have guessed that the coloured words are wrong. Choose the correct word from the box given below and write it next to the wrong word.
Answer:This story certainly looks funny. Clearly, the coloured words are wrong. Choosing the correct word from the given box and writing the same at the appropriate place, the story should be read as under:
As the sun rises Sumana wakes up. What a lovely morning! She washes her face fast in 2 minutes and runs out. She goes straight to the bird’s nest. She has been watching the eggs for the last few days. She was waiting for the baby birds to come out. But before she can blink her eyes, in a moment a cat jumps on the tree. ’The mother bird cries loudly and Sumana rushes to shoo away the cat. As the cat jumps, it hits the big green mango. Dhum!
In two seconds it is on the ground! Oh, how sad! The mango is still not fully ripe. It needed one more week to become sweet. Suddenly Sumana’s sister calls out— Are you still not hungry? Has your stomach clock gone to sleep? Come and eat hot upma for breakfast.
How Long does it Take?
1.Have you seen someone knitting a sweater? Or someone weaving a cloth? Do try to find out from a potter how long it takes to make a pot. Also tell us if you take hours or minutes to have your bath. (Is it years since you last had a bath? Ha, ha!). Think of many different things that can take different times. Make your table as long as you can.
Answer: The required table is as under:
2.Think of some other things, some faster and some slower. Make a long list.
Answer:
3.How many of you can speak and stamp at the same time.
Answer: Most of us can speak and stamp at the same time.
How Old are We?
Puzzle
1. Irfan’s mother is twice as old as him. She is also 20 years older than him. Guess the ages of Irfan and his mother.
Answer: Irfan’s age is 20 years and his mother’s age is 40 years.
Birth Certificate
1.Look at the birth certificate of bincy.
Answer:From the given certificate, we find:
(i) 2nd of May (ii) 6 years (iii) 50 years
(iv)2 May 2010 (v) 3 months (vi) 7 years
(vii) 3 months and 3 days (viii)815/02.
1.Find Out
•When were you born? .
•Write your date of birth in numbers.
•Do ybu have a birth certificate? Ask your parents and make one for yourself?
Answer: (a)12 Oct. 1993.
(b)12.10,1993.
(c)Yes, I have my birth certificate and it is as under
2.look at the calendar for the year 2006.
(i)How many months does a year have?———-
(ii)List the months which have 30 days. ———-
(iii)List the months which have 31 days.———-
(iv)How many days does the month of February have?———-
(v)How many days make a week?———-
(vi)How many weeks are there in July?———-
Is it true for all the months? ———-
(vii)In which month did you come to class III?———-
(viii)Make a circle on these dates in the Calender:
26th January, 14th November, 31st December.
Is there something special about these dates?
Answer: (i)Twelve.
(ii)April, June, September, November.
(iii) January? March, May, July, August, October, December.
(iv)28 or 29 (in the leap year).
(v)Seven.
(vi)Four, yes.
(vii) In the month of April.
(viii) Do as directed.
Yes, 26th January is Republic Day.
14th November is Children Day.
31st December is New Year Eve.
3.Fill in the blanks with the correct year:
2005, 2008, 2007, 2004, 2009, 2010
(i)Which year was it two year back?———-
(ii)In which year were you in class II? ———-
(iii)Which year will be the next year?———-
(iv)Which year will come after 3 years?———-
Answer: (i) 2004 (ii) 2005 (iii) 2007 (iv) 2010.
Which Festival Comes First?
1.Given below are some festivals we celebrate during the year. Look at the calendar (2006) to find the days on which these fall.
Answer:
2.Arrange the festivals in the order in which they come in the year.
Answer: 1. Pongal 2.Guru Ravidas’s Birthday
3.Milad-Ul-Nabi 4.Bihu
5.Raksha bandhan 6.Onam
7.Gandhi Jay anti 8.Diwali
9.Guru Nanak’s Birthday 10.Christmas Day.
3.Which festival comes in the beginning of the year?
Answer: Pongal.
4.Which festival comes at the end of the year?
Answer: Christmas.
Calendar Magic
Here is the calendar for the month of February 2007. Let us mark a square on the calendar and see some magic.February 2007
1.Which is the number in the centre of the square?
Answer: 13.
Join three numbers by drawing a line. The line must pass through the number at the centre.
2.How many such lines can you draw?
Answer: Four such lines can be drawn.
3.Add the three numbers on each of these lines. What do you notice?
Answer: 5 + 13 + 21 = 39 6 + 13 +20 = 39
7 + 13 + 19 = 39 12 + 13 + 14 = 39
On adding these numbers, it is noticed that the total of each such line is the same.
4.Now look at the calendar of 2006. Also look for the present month and draw any similar square in your notebook. Does the magic work for these?
Answer:The calendar of February 2006 is as under:
February 2006
Number 14 is in the centre of the square. On joining three numbers in a line we have.
On adding these numbers, we get
6 + 14 + 22 = 42
7 + 14 + 21 = 42
8 + 14 + 20 = 42
13 + 14 + 15 = 42
The total of each line is the same. Yes, the magic also works here.
5.Is this magic possible on a 10 x 10 number chart. Go to the Chapter ‘Fun with Numbers’ and check.
Answer: Let us select any two squares
In the first square we have
31 + 22 + 13 = 66
32 +’22 + 12 = 66
33 + 22 + 11 = 66
21 + 22 + 23 = 66
Therefore, magic works.
In the second square, we have
61 + 52 + 43 + 34 + 25 = 215
63 + 53 + 43 + 33 + 23 = 215
65 + 54 + 43 + 32 + 21 = 215
41 + 24 + 43 + 44 + 45 = 215
Therefore, magic also works here.
Complete the Calendar for August 2006
(i)Colour all the Sundays in red.
(ii)On which day does this month end?
(iii)Write the number of days in this month.
(iv)What day is it on 13th August?
(v)What is the date on second Saturday?
(vi)Is the 21st a Sunday?
(vii)What is the day on the 29th?
(viii)What will be the date on the same day next week?
(ix)How many Thursdays are there in this month?
Answer: Complete Calendar for August 2006 is as under:
(i)Do as directed. (ii)Thursday (iii)31
(iv) Sunday (v)12th (vi)No
(vii)Tuesday (viii)5th September (ix)Five.
Find Out!
(i)Which months in the calendar (2006) have 5 Sundays?
(ii)Is there any other day in any month which comes 5 times?
(iii)Can there be 6 Sundays in a month? Why?
Answer: (i) The months of January, April, July, October and December in the calendar 2006 have 5 Sundays.
(ii)Sunday, Monday, Tuesday in January 2006 comes 5 times.
Wednesday, Thursday, Friday, in March 2006 comes 5 times.
Sunday, Saturday in April 2006 comes 5 times.
Monday, Tuesday, Wednesday in May 2006;
Thursday, Friday in June 2006;
Sunday, Monday, Saturday in July 2006;
Tuesday, Wednesday, Thursday in August 2006;
Friday, Saturday in September 2006;
Sunday, Monday, Tuesday in October 2006;
Wednesday, Thursday in November 2006 and
Sunday, Friday, Saturday in December 2006 comes 2 times in these months.
(iii) Six Sundays cannot fall in a month as there are 4 or 5 weeks in a’month.
The True Story of Pedki Devi
1.Some things that happened in her life are given below. Mark these on her time line. For example, when she was 5 years old Pedki broke her foot. A is marked at 5 on the time line.
(A) Broke her foot (B) Lost one goat
(C) Got married (D) Had her fourth child
(E) First saw a police station (F) Learnt to read and write
(G) Eldest daughter got married.
Answer: After making the events on her time line. It will be as under:
2.Mark on the time line when she was born.
Answer: Position on line is marked as point P.
3.Make your own time line. Ask people around you and mark at least one thing that happened in each year of your life.
Answer:Events are marked against each year