Which of the following sentences are statements? Give reasons for your answer
(i) There are 35 days in a month
(ii) Mathematics is difficult
(iii) The sum of 5 and 7 is greater than 10
(iv) The square of a number is an even number
(v) The sides of a quadrilateral have equal length
(vi) Answer this question
(vii) The product of (−1) and 8 is 8
(viii) The sum of all interior angles of a triangle is `180^∘`
(ix) Today is a windy day
(x) All real numbers are complex numbers

Explanation

(i) The given sentence is: there are 35 days in a month. Since the maximum number of days in a month is 31, thus the given sentence is incorrect. Also, the sentence is said to be a statement when it is mathematically correct and if it is either true or false but not both. As the given sentence is false, thus it is a statement.


(ii)

The given sentence is: mathematics is difficult. For some people, mathematics is a difficult subject but for other people, it is a very easy subject, thus the sentence is subjective. As the given sentence is true as well as false, thus it is not a statement.


(iii)

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