Page 144 - Touchpad Mathematics_Ver1.0_C4

E:\Working\Orange_Education\TouchPad_Maths_4\Open_Files\Chap_08\Chap_08
\ 10-Nov-2025 Bharat Arora Proof-8 Reader’s Sign _______________________ Date __________

Patterns in Numbers Arranged in a Shape Century
21 st
Skills #Critical Thinking
Numbers can be arranged to form a shape or fit
inside a shape. These numbers can also have
patterns. Here are some numbers that have been 3 45
arranged as a rectangle. 9 37
example. Find the missing number. 6 8

Solution. On observing the figure closely, we find 18 7 ? 45
that each number in the smaller rectangle is the
difference of the two numbers outside it. 11 54
Now, we will observe these parts individually.

7 ?
3 45 18 45

9 37 11 54
6 8

Hence, the missing number = 54 – 45 = 9.

Exercise 8D

1. Find the pattern in each of the following and fill in the missing numbers:
a. 1, 4, 7, 10, 13, _____, _____, _____, _____

b. 512, 256, 128, _____, _____, _____, _____

2. Study the pattern and fill in the missing numbers:

a. b. c.
21 15 ? 36 7 5
32 48
? 9 2 9 18 13
12 8
3 8 11 ? 37 22
9 5
5 7 19 15

3. Study the pattern and write the next two steps.
a. 1 × 8 + 1 = 9 b. 0 × 9 + 1 = 1 c. 0 × 9 + 8 = 8

12 × 8 + 2 = 98 1 × 9 + 2 = 11 9 × 9 + 7 = 88

123 × 8 + 3 = 987 12 × 9 + 3 = 111 98 × 9 + 6 = 888

.................................. .................................. ..................................
.................................. .................................. ..................................

142 Mathematics 4