# Square and Cube Root- Aptitude Questions and Answers

 (0.324 * 0.081 * 4.624) / (1.5625 * 0.0289 * 72.9 * 64) is the square root of ? A) 24 B) 2.4 C) 0.024 D) 1.2 Correct Answer : 0.024 Explanation :(0.324 * 0.081 * 4.624) / (1.5625 * 0.0289 * 72.9 * 64) =(324 * 81 * 4624) / (1.625 * 289 * 729 * 64) =9/15625 hence,the square root is √(9/15625) =3/125 =0.024 √64 - √36, is equal to ? A) -2 B) 2 C) 1 D) 0 Correct Answer : 2 Explanation :√64 - √36 = 8- 6 = 2 6440 students were asked to stand in rows to form a perfect square. It was found that 40 students were left out. What will be the number of students in each row? A) 40 B) 80 C) 64 D) 60 Correct Answer : 80 Explanation :Remaining students = 6440- 40 = 6400 So, students in each row = √6400 = 80 What is √ { ( 0.064 * 6.25 ) / ( 0.081 * 4.84 ) } equal to? A) 10/99 B) 100/99 C) 9 D) 99 Correct Answer : 100/99 Explanation :√{ ( 0.064 * 6.25 )/( 0.081 * 4.84 ) } = √ {(64 * 625 )/( 81 * 484 ) } = (8 * 25)/( 9* 22) = 200/198 = 100/99 What is the smallest number by which 3087 must be divided so that the quotient is a perfect cube? A) 3 B) 21 C) 7 D) 9 Correct Answer : 9 Explanation :Factors of 3087 3087 = 3 × 3 × 7 × 7 × 7 = 32 × 73 here only 3 is not in the cube. Therefore 3 is the only number that is multiplied to make it a perfect cube. And divide it by 3 × 3 which is 9 to make it a perfect cube. The smallest number by which 1100 must be multiplied so that the product becomes a perfect square is____. A) 11 B) 5 C) 2 D) 10 Correct Answer : 11 Explanation :Prime factorization of 1100: 1100 = 2 x 2 x 5 x 5 x 11 => 2² x 5² x 11 In order to make it a perfect square, 1100 should be multiplied by 11 1100x11 = 2² x 5² x 11 x 11 = 2² x 5² x 11² = 12100. So the perfect square obtained by multiplying 1100 by 11 is 12100. The square root of obtained perfect square = √12100 = 2 x 5 x 11 = 110