CBSE - Linear Equations

1 Linear Equations 

Five years ago the sum of ages of the father and the son was 40 years. In present it's ratio is 4:1, then the present age of father is………..   

1) 30 yr  
2) 40 yr 
3) 45 yr 
4) 42 yr

2 Linear Equations 

A man can row three quarters of a km against the stream in   minutes and return in  minutes. The speed of man in still water is: 

1) 2 km/h  
2) 3 km/h 
3) 4 km/h 
4) 5 km/h   

3 Linear Equations 

In the equations 3x + 2y = 13xy  and 4x - 5y = 2xy, the value of x and y satisfy that the equations are

1)  ( 2, 3 )
2)  ( 3, 2 ) 
3)  ( 1/2, 1/3 ) 
4)  ( 1/3, 1/2 )

4 Linear Equations 

Sum of the digits of two digit number is 9. The number obtained by interchanging the digit is 18 more than twice the original number. The original number is: 

1)  72  
2)  27 
3)  36 
4)  63

5 Linear Equations 

Two numbers are in the ratio 3: 4. If 5 is subtracted from each .then the ratio will be 2:3. What is the smallest number?   

1)  15  
2)  18 
3)  20 
4)  24

6 Linear Equations 

The value of k for which the system of equations kx - y = 2, 6x - 2y = 3 has a unique solution, is_______.

1)  = 3 
2) ≠ 3 
3) ≠ 0 
4) = 0

7 Linear Equations 

In a two digit number, the number of ten’s place is double of the number of unit’s place. If we exchange the numbers mutually then the number decrease b 18, then the number is:- 

1) 24 
2) 36 
3) 39
4) 42 

8 Linear Equations 

If  x-y = 3 and x + y ≥ 9 the least value of  x is:  

1) 6  
2) 3 
3) 2 
4) 1

9 Linear Equations 

If the system of equation  3x+ y = 1, (2k—1)x + (k - 1)y = (2k + 1) , has no solution, then the value of k is: 

1) 2 
2) 3 
3) -2 
4) 1

10 Linear Equations 

The equations representing the given graph is _____.

1)  7x + 2y = 11; y - 2x = 3 
2) 2x + 7y = 11; 5x + (35y/2) = 25 
3) 3x - 7y = 10; 8y - 6x = 4 
4) 3x - 4y = 1; 8y - 6x = 4