Courses

# Test: Elimination Method

## 10 Questions MCQ Test Mathematics (Maths) Class 10 | Test: Elimination Method

Description
This mock test of Test: Elimination Method for Class 10 helps you for every Class 10 entrance exam. This contains 10 Multiple Choice Questions for Class 10 Test: Elimination Method (mcq) to study with solutions a complete question bank. The solved questions answers in this Test: Elimination Method quiz give you a good mix of easy questions and tough questions. Class 10 students definitely take this Test: Elimination Method exercise for a better result in the exam. You can find other Test: Elimination Method extra questions, long questions & short questions for Class 10 on EduRev as well by searching above.
QUESTION: 1

### The values of x and y which satisfy the equations: 47x + 31y = 63 and 31x + 47y = 15 are ____________​

Solution:

Given pair of linear equations:

47x+31y = 63  ---(1)

31x+47y = 15  ---(2)

multiply equation (1) by 31 and equation (2) by 47

substract (2) from (1) we get

(961 - 2209)y = 63x31 - 15x47

-1248 y = 1953 - 705

-1248 y = 1248

Therefore, y = -1.

Substitute y = -1 in equation (1) we get

47x = 94

So, x = 2.
Hence, The values of x and y are 2, -1.

QUESTION: 2

Solution:
QUESTION: 3

### A train overtakes two persons who are walking at the rate of 8 kmph and 12 kmph in the same direction in which the train is going, and passes them completely in 9 and 10 seconds respectively. What is the length of the train?

Solution:
QUESTION: 4

Adding 1 to the numerator and subtracting 1 from the denominator of a fraction makes it 1. However, if 1 is added only to the denominator of the fraction it becomes ½ . The fraction is______​

Solution:
QUESTION: 5

In elimination method _____________ is an important condition.​

Solution:

In the elimination method we equate either of the coefficient so that the other is eliminated ,substituting the value of one variable into the other equation and then we are left with the linear equation which is solvable and values of the variables are obtained.

QUESTION: 6

The value of x in mx + ny = c; nx – ny = c + 1 is​

Solution:
QUESTION: 7

The sum of the digits of a two digit number is 12. The number obtained by reversing its digits exceeds the given number by 18. Then the number is_____

Solution:

Let us assume x and y are the two digits of the number
Therefore, two-digit number is = 10x + y and the reversed number = 10y + x
Given:
x + y = 12
y = 12 – x  (1)
Also given:
10y + x - 10x – y = 18
9y – 9x = 18
y – x = 2    (2)
Substitute the value of y from Equation 1 in Equation 2
12 – x – x = 2
12 – 2x = 2
2x = 10
x = 5
Therefore, y = 12 – x = 12 – 5 = 7
Therefore, the two-digit number is 10x + y = (10*5) + 7 = 57

QUESTION: 8

If x = a, y = b is the solution of the equations x – y = 2 and x + y = 4, then the values of a and b are, respectively.

Solution:

Given, x=a and y=b.
Given equations, x-y=2( assume it as equation 1)
x+y=4( assume it as equation 2)

Equation 1+2,
x-y=2
x+y=4
- - - - - - -
2x=6( y gets cancelled as there is a negative y and a positive y implies y-y=0)
x=6/2
x=3
But x=a implies a=3
substitute a in equation 1 (it can be substituted even in equation 2)
x-y=2
3-y=2
y=3-2
y=1
But y=b implies b=1
Therefore, a=3 and b=1

QUESTION: 9

A lending library has a fixed charge for the first two days and an additional charge for each day thereafter. Sunil paid Rs 28 for a book kept for seven days, while Sohail paid Rs 32 for the book he kept for nine days. Find the charge for each extra day.​

Solution:
QUESTION: 10

At a closing down sale, a book store was selling 3 books and 5 notebooks for Rs 309 or 6 books and 2 notebooks for Rs 282. How much would one book and 1 notebook cost?​

Solution: