NCERT Exemplar Solutions
Class 7 - Mathematics - Unit 1: Number System - Multiple Choice QuestionsQuestion 12
Class 7 - Mathematics - Unit 1: Number System - Multiple Choice Questions
Question. 12
\((-11)\times 7\) is not equal to
(a)
\(11\times(-7)\)
(b)
\(-\,(11\times 7)\)
(c)
\((-11)\times(-7)\)
(d)
\(7\times(-11)\)
Detailed Answer with Explanation:
Idea: Remember these rules:
Negative × Positive = Negative
Negative × Negative = Positive
Target expression
((-11) imes 7)
= (-77)
Check each option
(a) (11 imes(-7))
= (-77)
Matches the target.
(b) (-,(11 imes 7))
(11 imes 7 = 77)
(-,77)
Matches the target.
(c) ((-11) imes(-7))
Negative × Negative = Positive
= (+77)
Does not match the target.
(d) (7 imes(-11))
= (-77)
Matches the target.
Conclusion: Only option (c) is not equal to ((-11) imes 7).