  We show that the recently found quartic action for the scalars from the
massless graviton multiplet of type IIB supergravity compactified on
AdS_5\times S^5 background coincides with the relevant part of the action of
the gauged N=8 5d supergravity on AdS_5. We then use this action to compute the
4-point function of the lowest weight chiral primary operators
$\tr(\phi^{(i}\phi^{j)})$ in N=4 SYM_4 at large $N$ and at strong `t Hooft
coupling.
