NCERT Exemplar Solutions
Class 7 - Mathematics - Unit 1: Number System - Multiple Choice QuestionsQuestion 21
Class 7 - Mathematics - Unit 1: Number System - Multiple Choice Questions
Question. 21
Which of the following does not represent an integer?
(a)
\(0\div(–7)\)
(b)
\(20\div(–4)\)
(c)
\((–9)\div 3\)
(d)
\((–12)\div 5\)
Detailed Answer with Explanation:
Idea: An integer is any whole number (…, −3, −2, −1, 0, 1, 2, 3, …). If a division gives a fraction or decimal (like −12/5 or −2.4), it is not an integer.
(a) (0 div (-7))
(0 div (-7))
= (0)
Zero is an integer.
(b) (20 div (-4))
(20 div (-4))
= (-5)
(-5) is an integer.
(c) ((-9) div 3)
((-9) div 3)
= (-3)
(-3) is an integer.
(d) ((-12) div 5)
((-12) div 5)
= (- rac{12}{5})
= (-2.4)
(- rac{12}{5}) (or (-2.4)) is not a whole number, so it is not an integer. ❌
Answer: (d)