Read this article and answer this question Prussia suffered several defeats in 1759. At the Battle of Kay, or Paltzig, the Russian Count Saltykov with 47,000 Russians defeated 26,000 Prussians commanded by General Carl Heinrich von Wedel. Though the Hanoverians defeated an army of 60,000 French at Minden, Austrian general Daun forced the surrender of an entire Prussian corps of 13,000 in the Battle of Maxen. Frederick himself lost half his army in the Battle of Kunersdorf , the worst defeat in his military career and one that drove him to the brink of abdication and thoughts of suicide. The disaster resulted partly from his misjudgment of the Russians, who had already demonstrated their strength at Zorndorf and at Gross-Jägersdorf , and partly from good cooperation between the Russian and Austrian forces.  However, disagreements with the Austrians over logistics and supplies resulted in the Russians withdrawing east yet again after Kunersdorf, ultimately enabling Frederick to re-group his shattered forces.
Who had more troops, the Russians or the Prussions?
Russians