Pressure acting over an area produces a force equal to pressure times area, so the same pressure on a larger area gives a larger total push. Pressure 6 Pa over area 3 m^2 gives force 6 times 3 = 18 N exactly for the stated toy force ledger; real soft tissues have nonuniform pressure, boundary-condition errors, anisotropy, and measurement uncertainty.
A pressure force is checked as pressure multiplied by area. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.