CBSE Class 3 Mathematics
NCERT Solutions
Chapter – 7
TIME GOES ON
NCERT Solutions
Chapter – 7
TIME GOES ON
PAGE 97
1. Think of some other things, some faster and some slower. Make a long list. Take seconds.
Ans. To throw a ball, to take a snap, to wear slippers, to switch on a light, to whistle, to skip a rope, to yawn, to squeeze a lemon, to slide on the swing.
Takes months
To grow wheat (some seed to big plant) – To make a movie
To change from summer to winter – For the earth to rotate
For a baby to come out its mother’s stomach – For glacier to melt
To construct a house – To write a book.
PAGE 98
2. Have you heard people playing a table or the drums? Find out a few different beats they play. Also ask what bols they say for the beats they play.
Ans. The bols are: Ta Tha Din Dha, Ta Tha Din Dha.
PAGE99
3. Irfan mother is twice as old as him. She is also 20 years older than him. Guess the ages of Irfan and his mother.
Ans. Irfan’s age is 20 years.
His mother’s age is 40 years.
PAGE 101
Find out
4. How many full moons have passed since you were born?
Ans. 87 full moons have passed since you were born.
PAGE 100
5. Look at the birth certificate of Bincy.
(a) 2/5/2002 shows that Bincy was born on 2___
(a) 2/5/2002 shows that Bincy was born on 2___
Ans. 2nd of May.
(b) How old will Bincy be on 2 May 2008?
Ans. 6 years.
(c) How old will she be in the year 2052?
Ans. 50 years.
(d) On what date will she be eight years old? Write in numbers.
Ans. 2 May 2010
(e) How many months old was Bincy on 2 August 2002?
Ans. 3 months.
(f) After how many months of her birth was the certificate issued?
Ans. 3 months and 3 days.
(g) What is the registration number of her certificate?
Ans. 815/02.
PAGE 103
6. Let us took at the calendar for the year 2006.
(a) How many months does a year have?
Ans. Twelve.
(b) List the months which have 30 days?
Ans. April, June, September, November.
(c) How many days does the month of February have?
Ans. January, March, May, July, August, October, December.
(d) How many days does the month of February have?
Ans. 28 days.
(e) How many days makes a week?
Ans. 7 days.
(f) How many weeks are there in July? Is it true for all the months?
Ans. Four, Yes.
(g) In which month did you come to class III?
Ans. April.
(h) Is there something special about these dates?
Ans. Yes.
7. Fill in the blanks with the correct answer:
2005 2008 2007 2004 2009 2010
(a) Which year was it two year back?
Ans. 2004.
(b) In which year were you in Class II?
Ans. 2005.
(c) Which year will be the next year?
Ans. 2007.
(d) Which year will come after 3 years?
Ans. 2010.
8. Look at the calendar (2006) to find out the days on which these fall?
Ans.
Festival
|
Date
|
Day
|
Diwali
|
October 21
|
Saturday
|
Pongal
|
January 14
|
Saturday
|
Raksha Bandhan
|
August 9
|
Wednesday
|
Gandhi Jayanti
|
October 2
|
Monday
|
Milad-Ul-Nabi
|
April 11
|
Tuesday
|
Onam
|
September 5
|
Tuesday
|
Guru Nanak Birthday
|
November 5
|
Sunday
|
Guru Ravidas Birthday
|
February 13
|
Monday
|
Christmas Day
|
December25
|
Monday
|
Bihu
|
April 14
|
Friday
|
PAGE 104
9. Which festival comes in the beginning of the year?
Ans. Pongal.
10. Which festival comes at the end of the year.
Ans. Christmas.
PAGE 105
11. 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?
Ans. The calendar of February 2006 is as under:
Number 14 is in the centre of square.
On joining three numbers in a line we have
6 + 14 + 22 = 42
7 + 14 +21 = 42
20 + 14 + 8 =42
13 +14 + 15 = 42
Yes, the magic also works here.
14. Can you find other magic patterns in the calendar?
Ans. Let us examine the addition of horizontal lines having seven numbers
4 + 5 + 6 + 8 + 10 = 49 = 1 x 49
11 + 12 + 13 + 14 + 15 + 16 + 17 = 98 = 2 x 49
18 + 19 + 20 + 21 + 22 + 23 + 24 = 147 = 3 x 49
25 + 26 + 27 + 28 + 29 + 30 + 31 = 196 + 4 x 49
Thus, each line is a multiple of 49.
15. Complete the calendar for August 2006?
Ans.
(a) On which day does this month end?
Ans. Thrusday.
(b) Write the number of days in this month.
Ans. 31 days.
(c) What day is it on 13 August?
Ans. Sunday.
(d) What is the date on the second Saturday?
Ans. 12.
(e) Is the 21 a Sunday?
Ans. No.
(f) What is the day on the 29 th? What will be the date on the same day next week?
Ans. Tuesday, 5 th September.
(g) How many thrusday are there in this month?
Ans. Five.
