NCERT Exemplar Solutions
Class 6 - Mathematics - Unit 7: Algebra - Multiple Choice Questions
Question 8

Question.  8

For any two integers x and y, which of the following suggests that operation of addition is commutative ?

(A)

x + y = y + x

(B)

x + y > x

(C)

x – y = y – x

(D)

x × y = y × x

Detailed Answer with Explanation:

  1. Meaning of “commutative”: The result does not change when we swap the order of the numbers.

  2. For addition, this means:

    ( x + y )

    has the same value as

    ( y + x )

  3. Example with numbers:

    ( 3 + 5 = 8 )

    ( 5 + 3 = 8 )

    Both give ( 8 ), so the order didn’t matter.

  4. Therefore, the statement that shows addition is commutative is:

    ( x + y = y + x )

Why the other options are not correct:

  • B: ( x + y > x ) — This only says the sum is bigger than one addend. It does not talk about swapping order.

  • C: ( x - y = y - x ) — Usually false (e.g., ( 7 - 2 = 5 ) but ( 2 - 7 = -5 )). Subtraction is not commutative.

  • D: ( x imes y = y imes x ) — This is about multiplication, not addition. The question asks about addition.

NCERT Exemplar Solutions Class 6 – Mathematics – Unit 7: Algebra – Multiple Choice Questions | Detailed Answers