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Find the smallest number by which each of the following numbersmust be multiplied to obtain a perfect cube.a. 2808b. 1323c. 128625d. 13720e. 68600​

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Answer:

e) 68600 is not a perfect cube. To make it a perfect cube we multiply it by 5. Thus, 68600 × 5 = 2 × 2 × 2 × 5 × 5 × 5 × 7 × 7 × 7 = 343000, which is a perfect cube. Observe that 343 is a perfect cube.

b) In order for 1323 to BECOME a perfect cube, we NEED to multiply it by 7. This will give US 9261 and the cube root will be 21. On dividing 1323 by 3 and 7 we get 3 X 3 x 3 x 7 x 7.



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