Question

. Is 243 a perfect cube ? *

2 points

Yes

No

2. Find the smallest number by which 243 must be multiplied to obtain a perfect cube . *

2 points

1

2

3

4

3. Find the smallest number by which 81 must be divided to obtain a perfect cube . *

2 points

1

2

3

4

4. Parikshit makes a cuboid of plasticine of sides 5 cm , 2 cm , 5 cm . How many such cuboids will he need to form a cube? *

2 points

17

18

19

20

5. find the cube root of 8000 ? *

2 points

60

20

80

40

6. find the cube root of 13824 by prime factorisation method . *

2 points

21

22

23

24

7. find the cube root of 64 by prime factorisation method . *

2 points

4

8

16

32

8. find the cube root of 512 by prime factorisation method . *

2 points

8

​

Answer 1

Answer:

it's too long question I can't understand

Answer 2

7.ANSWER IS HERE

So here we have to find cube root of 64 by using prime factorization.

we see all the factors are prime factors and

64=2×2×2×2×2×2

since 2 occurs in triples 64 is a perfect cube.

so the cube root of 64=2×2=4.

Note: An alternative method can be used by simply finding the factors bybreaking the numbers into smaller numbers and then taking the cube root.We are in a hurry and can make a mistake by writing 2 extra or one 2 less and hence we need to be careful while writing the prime factors