The following shows a sequence of perfect cube

64, p, 216, q

find the value of p+q

The sequence is as follows:

4^3, 5^3, 6^3, 7^3.

p = 5^3, q = 7^3

p + q = 468

I'd suggest you begin by listing actual perfect cubes, beginning with 4^3:

64, 125, 216, 343, etc. This is equivalent to 4^3, 5^3, 6^3, 7^3, etc.

Then p = 125, and q = 343. Thus, p + q = 125 + 343 = 468 (answer)