Use calendar (interlinking with patterns)
4th Maths : Term 3 Unit 4 : Time
Understanding Time Units
Now we will learn how 60 is used in time
\(60 \text{ seconds} = 1 \text{ minute}\)
\(60 \text{ minutes} = 1 \text{ hour}\)
\(1 \text{ hour} = 60 \times 60 = 3600 \text{ Seconds}\)
\(24 \text{ hours} = 1 \text{ day}\)
Normally 12 hours is used. But in Railways, airlines, armed forces and TV channels 24 hours are used.
Patterns in the Calendar
Now, learn the patterns in the Calendar.
Consider 2 X 2 square in the nearby month
Add the numbers in the following way so that you will get the same total as 18
\(5 + 13 = 18\)
\(12 + 6 = 18\)
3 X 3 Square Pattern
See the patterns in 3 X 3 square in the nearby month
Add the numbers in the following way so that you will get the same total as 51
\(9 + 17 + 25 = 51\)
\(23 + 17 +11 = 51\)
\(16 + 17 + 18 = 51\)
\(10 + 17 + 24 = 51\)
Note:
Calendar can teach us many things
Activity
Select any month and try to find 3 X 3 square and 2 X 2 square.
More Patterns
Let us see some more patterns in the following month.
Consider the line: 5 6 7 8 9 10 11
Middle number is 8
Sum of 5 and 11 is double the middle number (2x8) = 16
Sum of 6 and 10 is double the middle number (2x8) = 16
Sum of 7 and 9 is double the middle number (2x8) = 16
Try This
Select any month in a year. Find out the sum of any row and column. You wonder that the sum doubles the middle number.
\(10+18+26 =54\)
\(24+18+12 =54\)
\(17+18+19 =54\)
\(11 + 18 +25 =54\)
\(6+14 =20\)
\(13+7 =20\)