Selina solutions for Concise Mathematics [English] Class 8 ICSE chapter 1 - Rational Numbers [Latest edition]

Add, the pair of rational numbers, given below, and show that their addition (sum) is also a rational number

`(-5)/8 " and " 3/8`

Add, the pair of rational numbers, given below, and show that their addition (sum) is also a rational number

`(-8)/13 "and (-4)/13`

Add, the pair of rational numbers, given below, and show that their addition (sum) is also a rational number

`6/11 "and" (-9)/11`

Add, the pair of rational numbers, given below, and show that their addition (sum) is also a rational number

`5/(-26) "and" 8/39`

Add, the pair of rational numbers, given below, and show that their addition (sum) is also a rational number

`5/(-6) "and" 2/3`

Add, the pair of rational numbers, given below, and show that their addition (sum) is also a rational number

`(-2)  "and"  2/5`

Add, the pair of rational numbers, given below, and show that their addition (sum) is also a rational number

`9/(-4) " and" (-3)/8`

Add, the pair of rational numbers, given below, and show that their addition (sum) is also a rational number

`7/(-18) "and" 8/27`

Evaluate:

`5/9 + (-7)/6`

Evaluate:

`4 + 3/(-5)`

Evaluate:

`1/(-15) + 5/(-12)`

Evaluate:

`5/9 + 3/-4`

Evaluate:

`(-8)/9 + -5/12`

Evaluate:

`0 + (-2)/7`

Evaluate:

`5/(-11) + 0`

Evaluate:

`2 + (-3)/5`

Evaluate:

`4/(-9) + 1`

Evaluate:

`3/7 + (-4)/9 + (-11)/7 + 7/9`

Evaluate:

`2/3 + (-4)/5 + 1/3 + 2/5`

Evaluate:

`4/7 +0 + (-8)/9 + (-13)/7 + 17/9`

Evaluate:

`3/8 + (-5)/12 + 3/7 + 3/12 + (-5)/8 + (-2)/7`

For the pair of rational numbers, verify commutative property of addition of rational numbers:

`(-8)/7 "and" 5/14`

For the pair of rational numbers, verify commutative property of addition of rational numbers:

`5/9 "and" 5/-12`

For the pair of rational numbers, verify the commutative property of the addition of rational numbers:

`(-4)/5  "and"  (-13)/(-15)`

For the pair of rational numbers, verify commutative property of addition of rational numbers:

`2/(-5) "and" 11/(-15)`

For the pair of rational numbers, verify commutative property of addition of rational numbers:

`3  "and" (-2)/7`

For the pair of rational numbers, verify commutative property of addition of rational numbers:

`(-2) "and" 3/(-5)`

For each set of rational number, given below, verify the associative property of addition of rational number:

(i) `1/2 , 2/3 "and"-1/6`

For each set of rational number, given below, verify the associative property of addition of rational number:

(ii) `(-2)/5, 4/15 and (-7)/10`

For each set of rational number, given below, verify the associative property of addition of rational number:

(iii)  `(-7)/9,2/-3 and (-5)/18`

For each set of rational number, given below, verify the associative property of addition of rational number:

(iv) `-1, 5/6 and (-2)/3` 

Write the Additive Inverse(Negative) of : `(-3)/8`

Write the Additive Inverse(Negative) of : `4/(-9)`

Write the Additive Inverse(Negative) of : `(-7)/5`

Write the Additive Inverse(Negative) of : `(-4)/(-13)`

Write the Additive Inverse(Negative) of : 0

Write the Additive Inverse(Negative) of : -2

Write the Additive Inverse(Negative) of : 1

Write the Additive Inverse(Negative) of : `-1/3`

Write the Additive Inverse(Negative) of : `(-3)/1`

Fill in the blank:

Additive inverse of `(-5)/(-12)`=  --------

Fill in the Blank:

`(-5)/(-12)`+ its additive inverse = ______

Fill in the Blank

If `a/b` is additive inverse of `(-c)/d`, then `(-c)/d` is additive inverse of ------. 

State, True Or False

`7/9=(7+5)/(9+5)`

State, True Or False

`7/9=(-7-5)/(9-5)`

State, True Or False

`7/9=(7xx5)/(9xx5)`

State, True Or False

`7/9=(7÷5)/(9÷5)`

State, true or false 

`(-5)/(-12` is a negative rational number

State, true or false 

`(-13)/25` is smaller than `(-25)/13`

Evaluate:

`2/3 - 4/5`

Evaluate:

`(-4)/9 - 2/(-3)`

Evaluate:

`(-1) - 4/9`

Evaluate:

`(-2)/7 - 3/(-14)`

Evaluate:

`(-5)/18 - (-2)/9`

Evaluate:

`5/21 - (-13)/42`

Subtract:

`5/8` from `(-3)/8`

Subtract:

`(-8)/11 ` from `4/11`

Subtract:

`4/9` from `(-5)/9`

Subtract:

`1/4`from `(-3)/8`

Subtract:

`(-5)/8` from `(-13)/16`

Subtract:

`(-9)/22` from `5/33`

The sum of two rational numbers is `9/20`. If one of them is `2/5`, find the other. 

The sum of the two rational numbers is `(-2)/3`. If one of them is `(-8)/15` Find the other.

The sum of the two rational numbers is -6, If one of them is `(-8)/5`, Find the other.

Which rational numbers should be added to `(-7)/8` to get `5/9`?

Which rational number should be added to `(-5)/9` to get `(-2)/3`?

Which rational number should be subtracted from `(-5)/6` to get `4/9`?

What should be subtracted from -2 to get `3/8`?

What should be added to -2 to get `3/8`?

Evaluate:

`3/7+(-4)/9-(-11)/7-7/9`

Evaluate:

`2/3+(-4)/5-1/3-2/5`

Subtract:

`4/7-(-8)/9-(-13)/7+17/9`

Evaluate:

`(-14)/5 xx (-6)/7`

Evaluate:

`7/6 xx (-18)/91`

Evaluate:

`(-125)/72 xx 9/(-5)`

Evaluate:

`(-11)/9 xx (-51)/(-44)`

Evaluate:

`- 16/5 xx 20/8`

Multiply:

`5/6 "and" 8/9`

Multiply:

`2/7 "and" (-14)/9`

Multiply:

`(-7)/8 "and" 4`

Multiply:

`36/(-7) "and" (-9)/28`

Multiply:

`(-7)/10 "and" (-8)/15`

Multiply:

`3/(-2) "and" (-7)/3`

Evaluate:

`(2/(-3) xx 5/4) + (5/9 xx 3/(-10))`

Evaluate:

`(2xx1/4) - ((-18)/7 xx (-7)/15)`

Evaluate:

`(-5 xx 2/15) - (-6 xx 2/9)`

Evaluate:

`(8/5 xx (-3)/2) + ((-3)/10 xx 9/16)`

Multiply the rational number, given below, by one (1):

`7/(-5)`

Multiply the rational number, given below, by one (1):

`(-3)/(-4)`

Multiply the rational number, given below, by one (1):

0

Multiply the rational number, given below, by one (1):

`(-8)/13`

Multiply the rational number, given below, by one (1):

`(-6)/(-7)`

For the pair of rational numbers, given below, verify that the multiplication is commutative.

`(-1)/5 "and" 2/9`

For the pair of rational numbers, given below, verify that the multiplication is commutative.

`5/(-3) "and" 13/(-11)`

For the pair of rational numbers, given below, verify that the multiplication is commutative.

`3  "and" (-8)/9`

For the pair of rational numbers, given below, verify that the multiplication is commutative.

`0  "and" (-12)/17`

Write the Reciprocal (Multiplicative Inverse) of Rational Number, Given Below:

5

Write the Reciprocal (Multiplicative Inverse) of  Rational Number, Given Below:

-3

Write the Reciprocal (Multiplicative Inverse) of Rational Number, Given Below:

`5/11`

Write the Reciprocal (Multiplicative Inverse) of Rational Number, Given Below:

`(-7)/(-8)`

Write the Reciprocal (Multiplicative Inverse) of Rational Number, Given Below:

`(-8)/(-7)`

Write the Reciprocal (Multiplicative Inverse) of Rational Number, Given Below:

`15/(-17)`

Find the reciprocal(multiplicative inverse) of:

`3/5xx2/3`

Find the reciprocal(multiplicative inverse)of:

`(-8)/3xx13/(-7)`

Find the reciprocal (multiplicative inverse) of:

`(-3)/5xx(-1)/13`

Verify That`("x"+"y") xx"z"="x"xx"z"+"y"xx"z"`,If

`"x"=4/5,"y"=(-2)/3 and "z"=-4`

Verify that `("x"+"y")xx"z"="x"xx"z + y"xx"z",if`

`"x"=2," y"=4/5and "z"=3/(-10)`

Verify that `"x"xx("y"-"z")="x"xx"y"-"x"xx"z,"` if 

`"x"=4/5,"y"=-7/4and"z"=3`

Verify that `"x"=3/4,"y"=8/9and "z"=-5`

Name the multiplication property of rational number show below:

`3/5xx(-8)/9=(-8)/9xx3/5`

Name the multiplication property of rational number show below:

`(-3)/4xx(5/7xx(-8)/15)=((-3)/4xx5/7)xx(-8)/15`

Name the multiplication property of rational number show below:

`4/5xx(3/(-8)+(-4)/7)=4/5xx3/(-8)+4/5xx(-4)/7`

Name the multiplication property of rational number show below:

`(-7)/5xx5/(-7)=1`

Name the multiplication property of rational number show below:

`8/(-9)xx1=1xx8/(-9)=8/(-9)`

Name the multiplication property of rational number show below:

`(-3)/4xx0=0`

Fill the Blank:

The product of two positive rational numbers is always ……………

Fill in the blank:

The product of two negative rational numbers is always ……………

Fill in the blank:

If two rational numbers have opposite signs then their product is always …………..

Fill in the blank:

The reciprocal of a positive rational number is ………. and the reciprocal of a negative raitonal number is ……………

Fill in the blank:

Rational number 0 has ………….. reciprocal.

Fill in the blank:

The product of a rational number and its reciprocal is ………..

Fill in the blank:

The numbers ……….. and ……….. are their own reciprocals.

Fill in the blank:

If m is reciprocal of n, then the reciprocal of n is ………….

Evaluate:

`1 ÷ 1/3`

Evaluate:

`3 ÷ 3/5`

Evaluate:

`- 5/12 ÷ 1/16`

Evaluate:

`- 21/16 ÷ ((-7)/8)`

Evaluate:

`0 ÷ (- 4/7)`

Evaluate:

`8/(-5) ÷ 24/25`

Evaluate:

`-3/4 ÷ (-9)`

Evaluate:

`3/4 ÷ (-5/12)`

Evaluate:

`-5 ÷ (- 10/11)`

Evaluate:

`(-7)/11 ÷ ((-3)/44)`

Divide:

` 3  "by" 1/3`

Divide:

`-2  "by" (-1/2)`

Divide:

`0  "by" 7/(-9)`

Divide:

`(-5)/8  "by" 1/4`

Divide:

`- 3/4  "by" - 9/16`

The product of two rational numbers is -2. If one of them is `4/7`, find the other.

The product of two numbers is `(-4)/9`. If one of them is` (-2)/27`, find the other.

m and n are two rational number such that 

`"m"xx"n"=-25/9`

if `"m"=5/3`, find `"n"`.

`

m and n are two rational number such that

`"m"xx"n"=-25/9`

if `"n"=-10/9,`find `"m"`

By what number must `(-3)/4` be multiplied so that the product is `(-9)/16?`

By what number should `(-8)/13` be multiplied to get 16?

If `3 1/2` litres of milk costs ₹49, find the cost of one litre of milk?

Cost of `3 2/5` metre of cloth is ₹`88 1/2.` what is the cost of 1 metre of cloth?

Divide the sum of `3/7` and `(-5)/14` by `(-1)/2`

Find (m + n) ÷ (m - n), if:

m = `2/3` and n = `3/2`

Find (m + n) ÷ (m - n), if:

m = `3/4` and n = `4/3`

Find (m + n) ÷ (m - n), if:

m = `4/5` and n = `-3/10`

The product of  two rational numbers is -5.If one of these numbers is `(-7)/15`,find the other.

Divide the sum of `5/8` and `(-11)/12` by the difference of `3/7` and `5/14`.

Draw a number line and mark 

`3/4, 7/4, (-3)/4 and (-7)/4` on it.

Draw a number line and mark 

`2/3, (-8)/3, 7/3, (-2)/3 and -2`

Insert one rational number between 7 and 8

Insert one rational number between 3.5 and 5.

Insert one rational number between 2 and 3.2.

Insert one rational number between 4.2 and 3.6.

Insert one rational number between `1/2 and 2`.

Insert two rational numbers between 6 and 7.

Insert two rational numbers between 4.8 and 6∴

Insert two rational numbers between 2.7 and 6.3

Insert three rational numbers between 3 and 4

Insert three rational numbers between 10 and 12

Insert five rational numbers between `3/5` and `2/3`.

Insert six rational numbers between `5/6 and 8/9`.

Insert seven rational numbers between 2 and 3.