Involved in biosynthesis of fatty acids in mitochondria. a (3R)-hydroxyacyl-[ACP] + NADP(+) = a 3-oxoacyl-[ACP] + H(+) + NADPH Lipid metabolism; fatty acid biosynthesis. Present with 1760 molecules/cell in log phase SD medium. Belongs to the short-chain dehydrogenases/reductases (SDR) family.