What is the smallest number by which the following numbers must be multiplied, so that the products are perfect cubes?

(i) 675 (ii) 1323


(iii) 2560 (iv) 7803


(v) 107811 (vi) 35721

(i) 675


Factors of 675 = 3 × 3 × 3 × 5 × 5 = 33 × 52


Hence, to make a perfect cube we need to multiply the product by 5.


(ii) 1323


Factors of 1323 = 3 × 3 × 3 × 7 × 7 = 33 × 72


Hence, to make a perfect cube we need to multiply the product by 7.


(iii) 2560


Factors of 2560 = 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 5 = 23 × 23 × 23 × 5


Hence, to make a perfect cube we need to multiply the product by 5 × 5 = 25.


(iv) 7803


Factors of 7803 = 3 × 3 × 3 × 17 × 17 = 33 × 172


Hence, to make a perfect cube we need to multiply the product by 17.


(v) 107811


Factors of 107811 = 3 × 3 × 3 × 3 × 11 × 11 × 11 = 33 × 3 × 113


Hence, to make a perfect cube we need to multiply the product by 3 × 3 = 9.


(vi) 35721


Factors of 35721 = 3 × 3 × 3 × 3 × 3 × 3 × 7 × 7 = 33 × 33 × 72


Hence, to make a perfect cube we need to multiply the product by 7.


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