Question

If $a,b,c$ are rational numbers, then associativity of rational numbers under addition is given by
A. $a + b = b + a$
B. $a + \left( {b + c} \right) = \left( {a + b} \right) + c$
C. $a \times \left( {b \times c} \right) = \left( {a \times b} \right) \times c$
D. $a + \left( {b - c} \right) = \left( {a + b} \right) - c$

Answer 1

Hint: Make use of the standard definition of associative property of rational numbers under addition and then compare with the above given options to get the final answer.

Complete Step-by-Step solution:
Associative property of rational number under addition is given by following
$a + \left( {b + c} \right) = \left( {a + b} \right) + c$, where $a,b,c$ are rational numbers.
Therefore, Option B is correct.

Note: Just keep in mind that you can use the associative property with only addition and multiplication operations, but not subtraction or division, except in a few special cases.