Number System What least number shall be added to 4700 to make it a perfect square ? 81 91 71 61 81 91 71 61 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP (69)² = 4761 and (68)² = 4624Clerly 4624 < 4700 < 4761So 61 should be added to make 4700 a perfect square.
Number System If (83)² is subtracted from the square of a number, the answer so obtained is 8487. What is the number ? 146 179 163 124 146 179 163 124 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the number be x Therefore, x² - (83)² = 8487x² = 8487 + (83)²x² = 8487 + 6889x² = 15376Therefore, x² = 15376 x = 124
Number System If the difference between the squares of two consecutive numbers is 47, what is the smaller number ? 25 24 23 26 25 24 23 26 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be (x + 1) and x.Therefore, (x + 1)² - x² = 47x² + 2x + 1 - x² = 472x + 1 = 47Therefore, x = 46/2 = 23
Number System Which one of the following represents the sum of the first n even numbers? N2+ 1 N(N + 1) N2 N(N – 1) N2+ 1 N(N + 1) N2 N(N – 1) ANSWER EXPLANATION DOWNLOAD EXAMIANS APP N (N + 1)
Number System Pick the wrong number from the given number series. 3,4,10,33,135,685,4116 135 685 10 33 135 685 10 33 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP The correct number is 136.3 x 1 + 1 = 44 x 2 + 2 = 1010 x 3 + 3 = 3333 x 4 + 4 = 136136 x 5 + 5 = 685685 x 6 + 6 = 4116
Number System The sum of the two numbers is 12 and their product is 35. What is the sum of the reciprocals of these numbers? 12/35 35/8 1/35 7/32 12/35 35/8 1/35 7/32 ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Let the numbers be a and b. Then,a + b = 12 and ab = 35.(a + b)/ab = 12/35= (1/b + 1/a) = 12/35Sum of reciprocals of given numbers = 12/35.
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