NCERT Solutions for Class 3 Mathematics Chapter-10 Play With Patterns

Around Us
1.Look around you and list three things in which you find some patterns.
Ans. Staircase, Zebra crossing, Railing in a balcony.

2.Draw some patterns which you have found around yourself.
Ans.

3.Can you see a pattern in the way each block is repeated?

Ans. Yes, I can see that one block is placed upwards and the next is placed downwards.

Practice Time
Given below are some patterns.
1.Figure out the rule for each and continue the pattern.
Ans. (a) In this pattern; the colour of the pot changes from red to blue and then to red at each step.

(b) In this pattern A is written twice, followed by B written once.
AABAABAAB
(c)In this pattern; the number of petals increases from 1 to 3 and to 5. After that this sequence is repeated.
(d)In this pattern the blue colour is moving apticlockwise in steps of one.
(e) In this pattern; the figure is rotating clockwise in steps of one.
(f) In this pattern; the sequence of morning, afternoon, evening and night is repeated.
Morning, Afternoon, Evening, Night, Morning, Afternoon, Evening, Night

Growing Patterns
1.Can you see the rule and continue the pattern?
Ans. In this pattern; the number of marks in the oval is growing by one. After halfway mark the figure gets inverted.

Number Patterns
1.We have made some patterns with pictures. We can make patterns with numbers too. Like
21, 41, 61, 81, 101, 121
You know the next number, don’t you?
This series is growing by 20.
21, 41, 61, 81, 101,121, 141, 161, 181,
A.Look for the rules and continue these growing patterns:
(a)51, 56, 61, 66,————– ,———— ,————-
(b)7,————- ,21,28,35,————- ,————- ,————-
(c)2, 4, 8, 16, 32,————- ,————- , ————-
(d)12 A, 13 B, 14 C,————- ,————- ,————-
Ans. (a) 51, 56, 61, 66, 71, 76, 81, 86
(6) 7, 14, 21, 28,35, 42, 49, 56
(c) 2, 4, 8,16, 32, 64, 128, 256
(d) 12 A, 13 B, 14 C, 15 D, 16 E, 17 F.

B. Look at these growing patterns. Find out what to add to each number to get the next one.
(a)1, 3, 6, 10,———- ,————- ,————–
(b)0, 2, 6, 12,———- ,———–,————–
(c)1, 3, 7, 13,————–,———–, ————-
(d)2, 3, 6, 11,18,———— ,———–,————-
Ans. (a) Following sequence is observed in this pattern:
1 + 2 = 3 3 + 3 = 6 6 + 4=10
The number which is added in each step is growing by 1 Hence the pattern is as follows:
1, 3, 6,10, 15, 21, 28, 36, 45
(b)Following sequence is observed in this pattern:
0 + 2 = 2 2 + 4 = 6 6 + 6 = 12
The number which is added in each step is growing by 2.
Hence the pattern is as follows:
0, 2, 6, 12, 20, 30, 42, 56, 72
(c)Following sequence is observed in this pattern:
1 + 2 = 3
3+4=7
7 + 6 = 13
The number which is added in each step is growing by 2 Hence the pattern is as follows:
1, 3, 7, 13, 21, 31, 43, 57, 73 ’
(d) Following sequence is observed in this pattern:
2 + 1 = 3
3 + 3 = 6 6 + 5 = 11 11 + 7 = 18
The number which is added in each step is growing by 2 Hence the pattern is as follows:
2, 3, 6, 11, 18, 27, 38, 51, 66

Secret Messages
Amrita and Paritosh are writing secret messages:
3W3H3E3R3E 3A3R3E 3Y303U
3 I3 N 3T3H3E 3C3A3N3T3E3E3N
1.Can you tell what they are trying to say?
Ans. Following are the secret messages:Where are you?
In the canteen

3.There are two secret messages. Look at the patterns and find the hidden sentences.
1I2L204V5E6Y708U
Ans. The message is:I LOVE YOU

4.ATBHCIDSEBFOGOHKIIJSKFLUMN
Ans. The message is:
THIS BOOK IS FUN

5.Now you also make your own secret messages.
Ans.1 I 2 L 3 O 4 V 5 E 6 I 7 N8D9I10A I LOVE INDIA
AMBACNDMEOFHGAHNILJIKVLEMSNAOTPDQERLS
HTI
MANMOHAN LIVES AT DELHI

Even and Odd Number Patterns

Half these numbers are in yellow. What patterns do you see in these numbers? Continue the same pattern and fill in the blanks:
96, 98,100,102,104,106, IQS, 110,112,114
1.How far can you continue this pattern?
Ans. This pattern can be continued endlessly.
These numbers have a special name. They are called even numbers.

2.Do any of these even numbers end with 3 or 5?
Ans. None of the even numbers end with 3 or 5.

3.What do even numbers end with?
Ans. Even numbers end with 2, 4, 6, 8 or 10.

4.Look at the pattern of numbers in blue. Continue the pattern and fill in the blanks.
Ans. 99,101,103,105,107,100, 111, 113,115

5.What do the numbers in blue end with?
Ans.The numbers in blue end with 1, 3, 5, 7 or 9.

6.Write all odd numbers between 400 and 410.
Ans. 401, 403, 405, 407, 409.

7.Write all even numbers between 155 and 165.
Ans. 156,158,160,162,164.

8.If we add 1 to any odd number we get an————(even/odd) number.
Ans. If we add 1 to any odd number we get an even number.

9.If we add’l to any even number we get an————(even/odd) number.
Ans. If we add 1 to any even number we get an odd number.

10.What do you get if you add an even number to an odd number?
Ans. Odd number.

Names in an Order
Adil has to arrange this list so that the names starting with A comes first and then come those with B, C, D and so on. Number these names in the order in which they will come.

Jalaj is proud to have a special name. He says if you read it backwards it is still the same.
1.Which of the following names have the same pattern?
Harsh, Anna, Kanak, Munna, Ongbi
Ans. Anna and Kanak.