Question

Difference of two numbers which are perfect cubes is 189 if the cube root of the smaller of the two numbers is 3 find the cube root of the larger number

Answer 1

cube root of A=3
A=3^3
A=27
B-A=189
B=189+A=189+27=216
$\sqrt[3]{b} = \sqrt[3]{216} = 6$

Answer 2

Let the two nos be x and y

Now given -: Difference of two numbers which are perfect cubes is 189

⇒ x^3 - y^3 = 189

Let y be the smaller of the two nos

and the cube root of the smaller [y] of the two numbers is 3

⇒ y=3

find the cube of 3 and that is 27

⇒ y^3  = 27

ATP

⇒ x^3 - y^3 = 189

=> x^3 -27 =189  [Putting the value of y^3  = 27]

=> x^3 =189 +27

=> x^3= 216

Cube root of (216) = 6

x=6

Therefore, the larger number is 6. Ans

and the smaller number is  3   Ans