If the speed of light (c), acceleration due to gravity (g) and pressure (p) are taken as the fundamental quantities. The dimensional formula of gravitational constant is

Let  G ∝ cxgypzBy substituting the following dimensions:G = M−1L3T−2, c = LT−1, g = LT−2p = ML−1T−2And by comparing the powers of both sidesWe can get x = 0, y = 2. Z = -1∴   G ∝ c0g2p−1