" /> -->

#### Rational Numbers One Mark Questions

8th Standard EM

Reg.No. :
•
•
•
•
•
•

Maths

Time : 00:30:00 Hrs
Total Marks : 20
5 x 1 = 5
1. Multiplicative inverse of 0 (is)

(a)

0

(b)

1

(c)

-1

(d)

does not exist

2. Which of the following illustrates the inverse property for addition?

(a)

$\frac { 1 }{ 8 } -\frac { 1 }{ 8 } =0$

(b)

$\frac { 1 }{ 8 } +\frac { 1 }{ 8 } =\frac { 1 }{ 4 }$

(c)

$\frac { 1 }{ 8 } +0=\frac { 1 }{ 8 }$

(d)

$\frac { 1 }{ 8 } -0=\frac { 1 }{ 8 }$

3. Closure property is not true for division of rational numbers because of the number

(a)

0

(b)

-1

(c)

0

(d)

$\frac { 1 }{ 2 }$

4. $\frac { 1 }{ 2 } -\left( \frac { 3 }{ 4 } -\frac { 5 }{ 6 } \right) \neq \left( \frac { 1 }{ 2 } -\frac { 3 }{ 4 } \right) -\frac { 5 }{ 6 }$ illustrates that subtraction does not satisfy the ________ property for rational numbers.

(a)

commutative

(b)

closure

(c)

distributive

(d)

associative

5. $\left( 1-\frac { 1 }{ 2 } \right) \times \left( \frac { 1 }{ 2 } -\frac { 1 }{ 4 } \right) \div \left( \frac { 3 }{ 4 } -\frac { 1 }{ 2 } \right)$=

(a)

$\frac { 1 }{ 2 }$

(b)

$\frac { 3 }{ 4 }$

(c)

$\frac { 1 }{ 4 }$

(d)

$\frac { -1 }{ 2 }$

6. 5 x 1 = 5
7. The multiplicative inverse of $2\frac { 3 }{ 5 }$ is _____________

()

$\frac { 5 }{ 13 }$

8. If -3 x $\frac { -6 }{ 11 }$ = $\frac { -6 }{ 11 } \times x$ is _______________

()

-3

9. If distributive property is true for $\left( \frac { 3 }{ 5 } \times \frac { -4 }{ 9 } \right) +\left( x\times \frac { 15 }{ 17 } \right) =\frac { 3 }{ 5 } \times (y+z)$ then x, y, z are ________ , ________ and ________.

()

$\frac { 3 }{ 5 }$$\frac { -4 }{ 9 }$ and $\frac { 15 }{ 17 }$

10. If $x\times \frac { -55 }{ 63 } =\frac { -55 }{ 63 } \times x=1$ then x is called the _______________ of $\frac { 55 }{ 63 }$

()

Multiplicative Inverse

11. The multiplicative inverse of -1 is ________.

()

-1

12. 5 x 1 = 5
13. $\frac { -7 }{ 8 } \times \frac { -23 }{ 27 } =\frac { -23 }{ 27 } \times \frac { -7 }{ 8 }$ illustrates the closure property of rational numbers

(a) True
(b) False
14. Associative property is not true for subtraction of rational numbers.

(a) True
(b) False
15. The additive inverse of $\frac { -11 }{ -17 }$ is $\frac { 11 }{ 17 }$

(a) True
(b) False
16. The product of two negative rational numbers is a positive rational number.

(a) True
(b) False
17. The multiplicative inverse exists for all rational numbers

(a) True
(b) False
18. 5 x 1 = 5
19. $\left( \frac { 5 }{ 6 } +-1 \right) +\frac { -3 }{ 4 } =\frac { 5 }{ 6 } +\left( -1+\frac { -3 }{ 4 } \right)$

20. (1)

a rational number

21. $\frac { -1 }{ 3 } \left( \frac { 1 }{ 4 } +\frac { 2 }{ 3 } \right) =\left( \frac { -1 }{ 3 } \times \frac { 1 }{ 4 } \right) +\left( \frac { -1 }{ 3 } \times \frac { 2 }{ 3 } \right)$

22. (2)

does not exist

23. $\frac { -4 }{ 9 } \times \frac { 9 }{ -4 } =\frac { 9 }{ -4 } \times \frac { -4 }{ 9 } =1$

24. (3)

25. $\frac { 1 }{ 0 }$

26. (4)

distributive property of multiplication over addition

27. $\frac { 22 }{ 7 }$

28. (5)

multiplicative inverse property