Math, asked by ayeshashaikh89, 7 months ago

find the smallest number by which 100 must be multiplied to obtain a perfect cube​

Answers

Answered by ridhima07
3

Answer:

Answer should be 10...

Step-by-step explanation:

10 ×10 ×10 = 1000

So this way answer should be 10...

Hope my answer helped you all...!!!

Pls mark me as the Brainliest...

Answered by sadhana1012
1

Step-by-step explanation:

In the prime factorization of a

perfect cube every  prime factor occurs 3

times.

 

To determine

whether a number is a perfect cube or not proceed as follows:

1.Find the prime

factors of the given number.

2. Make Group of

3 equal prime factors.

3. If a group

contains only one or two equal prime factors then a given number is not a

perfect cube otherwise it is a perfect cube.

==========================================================

Solution:

 (i) Prime factors of 243 = (3 × 3 × 3) ×

3 × 3

 

Here, two 3s are left

which are not in a triplet. To make 243 a cube, one more 3 is required.so, we

multiply 243 by 3 to make it a perfect cube.

 

243 × 3 = (3 × 3

× 3) × (3 × 3 × 3) = 729 is a perfect cube.

Hence, the smallest

natural number by which 243 should be multiplied to make it a perfect cube is

3.

 

(ii) Prime factors of  256 = (2 × 2 × 2) ×( 2 × 2 × 2) ×

2 × 2

 

Here, two 2s are left

which are not in a triplet. To make 256 a cube, one more 2 is required. so, we

multiply 256 by 2 to make it a perfect cube

 

256 × 2 = (2 × 2

× 2) × (2 × 2 × 2) × (2 × 2 × 2) = 512 is a perfect

cube.

 

Hence, the smallest

natural number by which 256 should be multiplied to make it a perfect cube is

2.

 

(iii) Prime factors of

72 = (2 × 2 × 2) × 3 × 3

 

Here, two 3s are left

which are not in a triplet. To make 72 a cube, one more 3 is required. so, we

multiply 72 by 3 to make it a perfect cube.

 

72 × 3 = (2 × 2 ×

2) × (3 × 3 × 3) = 216 is a perfect cube.

Hence, the smallest

natural number by which 72 should be multiplied to make it a perfect cube is 3.

 

(iv)  Prime factors of 675 = (3 × 3 × 3) ×

5 × 5

Here, two 5s are left

which are not in a triplet. To make 675 a cube, one more 5 is required. so, we

multiply 675 by 5 to make it a perfect cube.

 

675 × 5 = (3 × 3

× 3 )× (5 × 5 × 5 )= 3375 is a perfect cube.

Hence, the smallest

natural number by which 675 should be multiplied to make it a perfect cube is

5.

 

(v) Prime factors of 100

= (2 × 2) × (5 × 5)

Here, two 2s and two

5s are left which are not in a triplet. To make 100 a cube, we require one more

2 and one more 5. so, we multiply 100 by (2 x5 =10) to make it a perfect cube

 

100 × 2 × 5 = (2

× 2 × 2) ×( 5 × 5 × 5)  = 1000 is a perfect cube

Hence, the smallest

natural number by which 100 should be multiplied to make it a perfect cube is 2

× 5 = 10.

 

(v) Prime factors of 100

= (2 × 2) × (5 × 5)

Here, two 2s and two

5s are left which are not in a triplet. To make 100 a cube, we require one more

2 and one more 5. so, we multiply 100 by (2 x5 =10) to make it a perfect cube

 

100 × 2 × 5 = (2

× 2 × 2) ×( 5 × 5 × 5)  = 1000 is a perfect cube

Hence, the smallest

natural number by which 100 should be multiplied to make it a perfect cube is 2

× 5 = 10.

 =========================================================

Hope this will help you....

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