Candidates can download NCERT Exemplar Class 8 Maths Unit 13 from this page. The exemplar has been provided by the National Council of Educational Research & Training (NCERT) and the candidates can check it from below for free of cost. It contains objective, very short answer type, short answer type, and long answer type questions. Along with it, the answer for each question has also been provided. From the NCERT Exemplar Class 8 Maths Unit 13, candidates can understand the level and type of questions that are asked in the exam.

## NCERT Exemplar Class 8 Maths Unit 13 Playing with Numbers

NCERT Class 8 Maths Unit 13 is for Playing with Numbers. The type of questions that will be asked from NCERT Class 8 Maths Unit 13 are displayed in the below provided NCERT Exemplar Class 8 Maths Unit 13. With the help of it, candidates can prepare well for the examination.

### Main Concepts and Results

- Numbers can be written in general form. For example, a two digit number ab is written as ab = 10a + b; a three digit number abc is written as abc = 100a + 10b + c
- The general form of numbers are helpful in solving various problems related to numbers.
- Rationale for the divisibility of numbers by 11, 10, 5, 2, 9 or 3 can be explained by writing the numbers in general form.
- Many number puzzles involving different letters for different digits are solved using rules of number operations.

### Solved Examples

**In examples 1 to 4, out of four options only one is correct. Write the correct answer.**

**In examples 5 to 7, fill in the blanks to make the statements true.**

**In examples 8 to 10, state whether the statements are true (T) or false (F).**

### Think and Discuss

- . What would be the value of y, if 277y is divisible by 11?

### Multiple Choice Questions

### Fill in the Blanks Type Questions

### True False Type Questions

### Short Answer Type Questions

### Applications, Games and Puzzles

**1. Polygonal Numbers**

Study the patterns given below and extend it. We already know about

square numbers.

Draw two more.

Here for the first square number, use 1² ; for the second square number, use 2² . To find the third square number use 3² and so on. Write the nth square number.

Now let’s move to triangular numbers.

Find the next triangular number.

o find the nth triangular number we use the formula

Are you familiar with pentagonal numbers?

First three are given to you. Write the next one

Draw the dot patterns for the next pentagonal number. Count the number of dots inside the entire shape and write the number under the shape.

2. Put tick mark in the appropriate boxes if the given numbers are divisible by any of 2, 3, 4, 5, 6, 8, 10, 11 numbers.

**3. Cross Number Puzzle**

Fill in the blank spaces in the cross number puzzle using following clues.

**Down**

(a) 59 ______ 63 ÷ 33

(b) 81 ______ 42 ÷ 6

(c) 7 ______ 6988 ÷ 11

(d) 37604 ______ 5 ÷ 15

(e) 56 ______ ÷ 10

**Across**

(f) 90 ______ 815 ÷ 15

(g) 3514 ______ ÷ 12

(h) 4 ______ 07 ÷ 7

(i) 8 ______ 558 ÷ 6

(j) 6 ______ 5 ÷ 55

Click here to download the NCERT Exemplar Class 8 Maths Unit 13 Playing with Numbers

### Answers to Multiple Choice Questions

**Activity**

**1**. 3, 5, 9**2.** 2, 3, 6, 9**3**. 2, 5, 10**4.** 2, 3, 6, 9, 11**5**. 2, 4, 8

MATHS

SCIENCE