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All questions of Rational Numbers for Class 8 Exam
= 
The cost of 
metres of cloth is 
. What is the cost of one metre of cloth?- a)
. - b)
- c)
- d)
Correct answer is option 'B'. Can you explain this answer?
The cost of metres of cloth is . What is the cost of one metre of cloth?
metres of cloth is . What is the cost of one metre of cloth?a)
.b)
c)
d)
 | Ananya Das answered |
Cost of one metre of cloth = 
In a school 5/8 of the students are boys. If the number of girls are 270. What is the number of boys in the school?- a)440
- b)450
- c)420
- d)400
Correct answer is option 'B'. Can you explain this answer?
In a school 5/8 of the students are boys. If the number of girls are 270. What is the number of boys in the school?
a)
440
b)
450
c)
420
d)
400
 | Kavya Saxena answered |
No. of girls = 1 - 5/8 = 3/8
Let x be the total no. of students then
x = 720
No. of boys = 720 - 270 = 450
Let x be the total no. of students then
x = 720
No. of boys = 720 - 270 = 450
=
m has been cut into 26 pieces of equal length. What is the length of each piece?
Which rational number is in between -2/3 and -1/4?- a)-5/24
- b)-5/12
- c)5/12
- d)None of these
Correct answer is option 'A'. Can you explain this answer?
Which rational number is in between -2/3 and -1/4?
a)
-5/24
b)
-5/12
c)
5/12
d)
None of these
 | Shubham Sharma answered |
ANSWER :- d
Solution :- If a and b are two Rational numbers then a rational number between them is ( a + b )/2
Rational number between -2/3 and -1/4 = [ (-2/3) + (-1/4)]/2
= [ ( -8 - 3 )/12]/2
= [(-11)/12]/2
= -11/24
Which number is smallest among 
- a)-5/6
- b)-7/12
- c)-5/8
- d)23/-24
Correct answer is option 'D'. Can you explain this answer?
Which number is smallest among
a)
-5/6
b)
-7/12
c)
-5/8
d)
23/-24
 | Geetika Shah answered |
LCM of 12, 6, 18, 24 = 72
The sum of two numbers is -4/3 If one of them is –5 then what is the other number?- a)11/3
- b)-11/3
- c)16/3
- d)19/3
Correct answer is option 'A'. Can you explain this answer?
The sum of two numbers is -4/3 If one of them is –5 then what is the other number?
a)
11/3
b)
-11/3
c)
16/3
d)
19/3
| | Kaavya Mishra answered |
Given information:
The sum of two numbers is -4/3.
One of the numbers is -5.
Let's solve the problem step by step:
Step 1: Assign variables
Let's assume the other number is x.
Step 2: Write the equation
According to the given information, the sum of the two numbers is -4/3. So, we can write the equation as:
-5 + x = -4/3
Step 3: Solve the equation
Add 5 to both sides to isolate x:
x = -4/3 + 5
x = -4/3 + 15/3
x = 11/3
Step 4: Answer the question
Therefore, the other number is 11/3. So, the correct answer is option 'A' - 11/3.
The sum of two numbers is -4/3.
One of the numbers is -5.
Let's solve the problem step by step:
Step 1: Assign variables
Let's assume the other number is x.
Step 2: Write the equation
According to the given information, the sum of the two numbers is -4/3. So, we can write the equation as:
-5 + x = -4/3
Step 3: Solve the equation
Add 5 to both sides to isolate x:
x = -4/3 + 5
x = -4/3 + 15/3
x = 11/3
Step 4: Answer the question
Therefore, the other number is 11/3. So, the correct answer is option 'A' - 11/3.
Closure property of rational number will be value in:- a)Addition
- b)Subtraction
- c)Multiplication
- d)All of these.
Correct answer is option 'D'. Can you explain this answer?
Closure property of rational number will be value in:
a)
Addition
b)
Subtraction
c)
Multiplication
d)
All of these.
| | Shubham Sharma answered |
Closure property of rational numbers is satisfied for addition, subtraction and multiplication.
Closure property : The sum of two rational numbers will be a rational of addition for rational number.
Closure property : The sum of two rational numbers will be a rational of addition for rational number.
What is additive inverse of -7/9?- a)7/9
- b)-9/7
- c)9/7
- d)1
Correct answer is option 'A'. Can you explain this answer?
What is additive inverse of -7/9?
a)
7/9
b)
-9/7
c)
9/7
d)
1
| | Amit Sharma answered |
If x is the additive inverse then 
x = 7/9
x = 7/9
How many rational numbers lie between 1/5 and 1/3?- a)One
- b)Two
- c)Three
- d)Infinite numbers
Correct answer is option 'D'. Can you explain this answer?
How many rational numbers lie between 1/5 and 1/3?
a)
One
b)
Two
c)
Three
d)
Infinite numbers
 | Jithin Ghosh answered |
Explanation:
To determine the number of rational numbers that lie between 1/5 and 1/3, we need to find the rational numbers with denominators between 5 and 3.
Finding the Rational Numbers:
To find the rational numbers between 1/5 and 1/3, we need to find the fractions with denominators between 5 and 3.
Finding the Smallest Rational Number:
The smallest rational number that lies between 1/5 and 1/3 can be found by taking the average of the two given numbers.
Average = (1/5 + 1/3) / 2 = 8/30 = 4/15
So, the smallest rational number that lies between 1/5 and 1/3 is 4/15.
Finding the Largest Rational Number:
The largest rational number that lies between 1/5 and 1/3 can be found by taking the average of the two given numbers.
Average = (1/5 + 1/3) / 2 = 8/30 = 4/15
So, the largest rational number that lies between 1/5 and 1/3 is also 4/15.
Finding the Number of Rational Numbers:
Since the smallest and largest rational numbers between 1/5 and 1/3 are the same, it means that there is an infinite number of rational numbers between 1/5 and 1/3.
This is because we can always find a rational number that lies between any two rational numbers by taking their average. In this case, the average is the same for both the smallest and largest rational numbers, which means there are infinitely many rational numbers between them.
Therefore, the correct answer is option 'D' - Infinite numbers.
To determine the number of rational numbers that lie between 1/5 and 1/3, we need to find the rational numbers with denominators between 5 and 3.
Finding the Rational Numbers:
To find the rational numbers between 1/5 and 1/3, we need to find the fractions with denominators between 5 and 3.
Finding the Smallest Rational Number:
The smallest rational number that lies between 1/5 and 1/3 can be found by taking the average of the two given numbers.
Average = (1/5 + 1/3) / 2 = 8/30 = 4/15
So, the smallest rational number that lies between 1/5 and 1/3 is 4/15.
Finding the Largest Rational Number:
The largest rational number that lies between 1/5 and 1/3 can be found by taking the average of the two given numbers.
Average = (1/5 + 1/3) / 2 = 8/30 = 4/15
So, the largest rational number that lies between 1/5 and 1/3 is also 4/15.
Finding the Number of Rational Numbers:
Since the smallest and largest rational numbers between 1/5 and 1/3 are the same, it means that there is an infinite number of rational numbers between 1/5 and 1/3.
This is because we can always find a rational number that lies between any two rational numbers by taking their average. In this case, the average is the same for both the smallest and largest rational numbers, which means there are infinitely many rational numbers between them.
Therefore, the correct answer is option 'D' - Infinite numbers.
km/hr. How much distance it will cover in
hour?
?
?
What is the additive inverse of 
?- a)17/60
- b)-17/60
- c)60/17
- d)-60/17
Correct answer is option 'B'. Can you explain this answer?
What is the additive inverse of ?
?a)
17/60
b)
-17/60
c)
60/17
d)
-60/17
| | Anita Menon answered |
Additive inverse of 17/60 is -17/60.
What should be added to -3/5 to get -1/3?- a)4/5
- b)2/5
- c)4/15
- d)8/15
Correct answer is option 'C'. Can you explain this answer?
What should be added to -3/5 to get -1/3?
a)
4/5
b)
2/5
c)
4/15
d)
8/15
| | Ananya Das answered |
Let x should be added.
If x is a non-zero rational number, then what is the value of x°?- a)1
- b)0
- c) -1
- d)Not defined .
Correct answer is option 'A'. Can you explain this answer?
If x is a non-zero rational number, then what is the value of x°?
a)
1
b)
0
c)
-1
d)
Not defined .
 | EduRev Class 8 answered |
According to the rules of exponents, any non-zero number raised to the power of zero is equal to 1. This rule applies regardless of whether the number is rational or irrational, as long as it is not zero.
- x is a non-zero rational number.
- x° = 1.
Therefore, the value of x° is 1.
Which number is largest among 
- a)7/-18
- b)4/-9
- c)-5/12
- d)-2/3
Correct answer is option 'A'. Can you explain this answer?
Which number is largest among
a)
7/-18
b)
4/-9
c)
-5/12
d)
-2/3
 | Get Idea answered |
To determine which fraction is the largest, we convert each to a decimal
: - A: 7/-18 ≈ -0.388
- B: 4/-9 ≈ -0.444
- C: -5/12 ≈ -0.4167
- D: -2/3 ≈ -0.6667
Among these, A (-0.388) is the closest to zero, making it the largest number.
The value of (5/4) – (8/3) is:- a)17/12
- b)- 17/12
- c)12/17
- d)-12/17
Correct answer is option 'B'. Can you explain this answer?
The value of (5/4) – (8/3) is:
a)
17/12
b)
- 17/12
c)
12/17
d)
-12/17
 | Vp Classes answered |
Explanation: 5/4 – 8/3
Making the denominator equal:
[(5/4) x (3/3)] – [(8/3) x (4/4)]
= (15/12) – (32/12)
= (15 – 32)/12
= -17/12
The sum of two numbers is 24 and their difference is 10, then,
number, y = 2nd number].- a)27/18
- b)17/7
- c)118/16
- d)14/34
Correct answer is option 'B'. Can you explain this answer?
The sum of two numbers is 24 and their difference is 10, then, number, y = 2nd number].
a)
27/18
b)
17/7
c)
118/16
d)
14/34
 | Coders Trust answered |
x + y = 24
The difference between x and y is 10. In other words, x minus y equals 10 and can be written as equation B:
x - y = 10
Now solve equation B for x to get the revised equation B:
x - y = 10
x = 10 + y
Then substitute x in equation A from the revised equation B and then solve for y:
x + y = 24
10 + y + y = 24
10 + 2y = 24
2y = 14
y = 7
Now we know y is 7. Which means that we can substitute y for 7 in equation A and solve for x:
x + y = 24
x + 7 = 24
x = 17
So x/y = 17/7
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