Let us consider Example 2 in Section 3.3, i.e.,the cost of 2 pencils and 3 erasers is Rs. 9 and the cost of 4 pencils and 6 erasers is Rs. 18. Find the cost of each pencil and each eraser

Solution:

Let the cost of pencils be Rs x and the cost of erasers be Rs y.

⇒ 2x + 3y = 9 be equation (1)

⇒ 4x + 6y = 18 be equation (2)

From equation (1) 2x + 3y = 9

x = (9 - 3y)/ 2

Substitute the value in equation 2,

4 [(9 - 3y)/ 2] + 6y = 18

2 (9 - 3y) + 6y = 18

18 - 6y + 6y = 18

18 = 18

Since there is no specific value of y, thus the value of x can not be obtained.

The statement is true for all the values of y and has infinitely many solutions.

☛ Check: NCERT Solutions for Class 10 Maths Chapter 3

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Let us consider Example 2 in Section 3.3, i.e.,the cost of 2 pencils and 3 erasers is Rs. 9 and the cost of 4 pencils and 6 erasers is Rs. 18. Find the cost of each pencil and each eraser

Summary:

There is no specific cost of pencil and erasers if the cost of 2 pencils and 3 erasers is Rs 9 and the cost of 4 pencils and 6 erasers is Rs 18

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☛ Related Questions:

• Let us consider the Example 3 of Section 3.2. Will the rails cross each other?
• The ratio of incomes of two persons is 9 : 7 and the ratio of their expenditures is 4 : 3. If each of them manages to save Rs 2000 per month, find their monthly incomes
• Use elimination method to find all possible solutions of the following pair of linear equations : 2x + 3y = 8 (1) 4x + 6y = 7(2)