Question

help please math cube and cube root class 8​

Answer 1

Ans1. since 3 × 5 × 7 × 11 are unpaired 259875 should be divided by 3 × 5 × 7 × 11 we get.

pairs for cube root = 3 × 5.

since 7 is unpaired so 259875 should be divided by 7 to get a perfect cube 259875 / 7 = 37125.

and the cube root of 37125 is 33.359

Ans2. Side of a cube = a

volume = a^3 = 21952m^3

a = 3√21952

a = 28

Ans3. Let the numbers be 4x and 5x.

(5x)^3-(4x)^3 = 61

=> (125)x^3-(64)x^3=61

=> (61)x^3=61

=> (x)^3=61/61

=> (x)^3=1

=> x=1

Since the numbers we have taken are 4x and 5x,

So,

4*x = 4*1 = 4.

5*x = 5*1 = 5.

Hence the required numbers are 4 and 5.

Ans4. in the upper

Ans5. The cube root of 19.683 is 2.7 because 2.7 × 2.7 × 2.7 = 19.683.

hope it hels you thanks