Closure Property of Rational Numbers

Q.

The multiplication of two irrational numbers is always an irrational number.

1. False

2. True

Q.

Sum of two irrational numbers is always irrational.

1. a^mn

2. a^m/n

Q.

What is the shortcut to identify the terminating and non-terminating numbers by seeing the question.

Q.

ABC+ABC+ABC=BBB

Find A, B , C

With proper method.

Q.

Question 4
Which of the following is not true?
(a) rational numbers are closed under addition.
(b) rational numbers are closed under subtraction.
(c) rational numbers are closed under multiplication.
(d) rational numbers are closed under division.

Q. Question 77
Rational numbers are closed under addition and multiplication but not under subtraction.

Q.

Which of the following is not true?

1. rational numbers are closed under addition.

2. rational numbers are closed under subtraction.

3. rational numbers are closed under multiplication.

4. rational numbers are closed under division.

Q.

0.00024 in standard form will be-

(a) 24×10^-5

(b) 2.4×10³

(c) 2.4×10^-4

(d) 24×10^-3

Q.

___________ is neither a positive nor a negative rational number.

1. Zero

2. 2

3. 1

4. 3

Q.

A non-terminating decimal number can either be rational or irrational number.

1. True

2. False

Q.

When we add zero to a whole number, the sum changes to___________

1. Irrational number

2. Whole number

3. Non-integer

4. Negative number

Q.

Name the property involved in the following example. 3/7×1=3/7=1×3/7

Q.

Which of the following rational number can be represented as terminating and which as non terminating decimals? give the answer without actual dividing

1- 13/8

2- -7/15

Q.

Identify the rational number which is different from the other three. Explain your reasoning

-5/11, -1/2, -4/9, -7/3

Q.

Verify that the set of integers $Z$ is closed under addition and multiplication. Also check if $Z$ is closed under subtraction and division.

Q.

Express 5.371 in the form of p/q

Q.

A cyclist moves with a speed of $\frac{4}{5}$ km\hr. How much distance will he cover in $2\frac{1}{2}$ hrs.

1. 3 km

2. 2 km

3. 1.5 km

4. 2.5 km

Q.

In between two rational number there is/are ----------

Q.

If $\frac{4}{5}÷\frac{-2}{3}$ follows closure property of division then the resultant number ____ is a Rational number.

1. = $\frac{6}{5}$

2. = $\frac{-6}{5}$

3. = $\frac{-5}{6}$

4. = $\frac{-8}{5}$

Q.

0.0000000798 can be expressed in standard form as

1. 7.98 × 10⁸

2. 7.98 × 10⁹

3. 7.98 × 10^-9

4. 7.98 × 10^-8

Q.

The division of rational numbers does not follow which of the following properties :

1. Associative

2. Distributive

3. Closure

4. Commutative

Q.

Question 4
Which of the following is not true?
(a) rational numbers are closed under addition.
(b) rational numbers are closed under subtraction.
(c) rational numbers are closed under multiplication.
(d) rational numbers are closed under division.

Q.

The following subtraction : $\frac{-5}{6}-\frac{8}{9}$ follows the closure property.

1. True

2. False

Q.

Division of two rational numbers is a rational number if denominator is not equal to zero.Justify.

Q.

Question 3
The numerical expression $\frac{3}{8}+\frac{(-5)}{7}=\frac{-19}{56}$ shows that:
(a) rational numbers are closed under addition.
(b) rational numbers are not closed under addition.
(c) rational numbers are closed under multiplication.
(d) addition of rational numbers is not commutative.

Q.

H.C.F. of 1.20 and 22.5 is

1. 0.03

2. 3

3. 0.003

4. 0.3

Q. In order to convert a rational number into its standard form, why do we need to make the denominator positive?

Q. Question 11(v)
The product of two rational numbers is always a _______.

Q.

Find the following by using appropriate property

3/5×(-2/5)+5/2(-3/5)×1/6

Q.

What are a truth table and its significance?