Numbers

7 : Which one of the following can not be the square of a natural number? A. 128242 B. 128881 C. 130321 D. 131044 Answer: Option A Explanation: Square of a natural number cannot end with 2. Hence 128242 cannot be the square of a natural number 8 : -88×39+312=? A. -3120 B. -3200 C. 3120 D. 3200 Answer: Option A Explanation: Again a question on basic arithmetic. Many algebraic formulas and Vedic Maths methods can help you to solve such questions quickly. -88×39+312=-3432+312=-3120 9 : How many prime numbers are there less than 40? A. 11 B. 12 C. 10 D. 13 Answer: Option B Explanation: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37 are the prime numbers less than 40. 10 : If J and L are odd numbers, then which of the following is even? A. J+L B. JL C. J + L + 1 D. JL + 2 Answer: Option A Explanation: Hence J + L is an even number or Just take any two odd numbers, say 1 and 3 J + L = 1 + 3 = 4 = an even number J + L + 1 = 1 + 3 + 1 = 5 = an odd number JL = 1 × 3 = 3 = an odd number JL + 2 = (1 × 3) + 2 = 5 = an odd number

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