What is the smallest number by which 2916 should be divided so that the quotient is perfect cube?
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(i)81 Prime factors of 81 = 3\times3\times3\times3 Here one factor 3 is not grouped in triplets. Therefore 81 must be divided by 3 to make it a perfect cube. (ii) 128 Prime factors of 128 = 2\times2\times2\times2\times2\times2 Here one factor 2 does not appear in a 3’s group. Therefore, 128 must be divided by 2 to make it a perfect cube. (iii) 135 Prime factors of 135 = 3\times3\times3\times5 Here one factor 5 does not appear in a triplet. Therefore, 135 must be divided by 5 to make it a perfect cube. (iv) 192 Prime factors of 192 = 2\times2\times2\times2\times2\times3 Here one factor 3 does not appear in a triplet. Therefore, 192 must be divided by 3 to make it a perfect cube. (v) 704 Prime factors of 704 = 2\times2\times2\times2\times2\times2\times11 Here one factor 11 does not appear in a triplet. Therefore, 704 must be divided by 11 to make it a perfect cube. Step-by-step explanation: Prime factorising 2916, we get, 2916=2×2×3×3×3×3×3×3 =2 2 ×3 6 . We know, a perfect cube has multiples of 3 as powers of prime factors. Here, number of 2’s is 2 and number of 3’s is 6. So we need to multiply another 2 in the factorization to make 2916 a perfect cube. Hence, the smallest number by which 2916 must be multiplied to obtain a perfect cube is 2. please mark it brainliest 1. Perfect Square: A natural number x is a perfect square if there exists a natural number y such that x=y2. In other words, a natural number x is a perfect square, if it is equal to the product of a number with itself. 2. Properties of Squares Numbers: (i) A number ending in 2, 3, 7, or 8 is never a perfect square. (ii) The number of zeroes in the end of a perfect square is never odd. So, a number ending in an odd number of zeroes is never a perfect square. (iii) Squares of even numbers are always even. (iv) Squares of odd numbers are always odd. 3. General Properties of Perfect Squares: (i) For any natural number n, we have n2= (Sum of first n odd natural numbers) (ii) The square of a natural number, other than 1, is either a multiple of 3 or exceeds a multiple of 3 by 1 . (iii) The square of a natural number, other than 1, is either a multiple of 4 or exceeds a multiple of 4 by 1. (iv) There are no natural numbers p and q such that p2=2q2 4. Pythagorean Triplets: For any natural number n greater than 1, (2n, n2−1, n2+1), is a Pythagorean triplet. 5. Square roots: The square root of a given natural number n is that natural number which when multiplied by itself gives n as the product and we denote the square root of n by n. Thus, n=m⇔n=m2. 6. Finding Square Roots: (i) In order to find the square root of a perfect square, resolve it into prime factors; make pairs of similar factors and take the product of prime factors, choosing one out of every pair. (ii) For finding the square root of a decimal fraction, make the even number of decimal places by affixing a zero, if necessary; mark off periods and extract the square root; putting the decimal point in the square root as soon as the integral part is exhausted. 7. Properties of Square Roots: For positive numbers a and b, we have (i) ab=a×b (ii) ab =ab Is 2916 a perfect cube?2916 doesn't have a perfect cube.
What is the smallest number by which we divide 6912 so that the quotient becomes a perfect cube find the cube root of the quotient?Given: A number 6912 . To do: To find the smallest number by which 6912 must be divided so that the number formed is a perfect cube. Therefore, we should divide 6912 by 22=4 2 2 = 4 , the smallest number to get 1728 which is a cube of 12 .
What is the smallest number by which 1458 should be divided so that the quotient is a perfect cube?The smallest number by which 1458 must be divided to make a perfect cube is 2.
What is the smallest number by which 1715 should be divided so that the quotient is a perfect?In other words, 1715 should be divided by 5 (the smallest number) so that the quotient is a perfect cube (343).
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