Edtech firm PhysicsWallah will acquire an additional 11% stake in civil services coaching platform Sarrthi IAS for Rs 71.8 crore, taking its holding to 51% and making the company a subsidiary.PhysicsWallah’s board approved the second tranche of the acquisition on July 16, along with revisions to the valuation methodology and purchase consideration for this leg of the deal, according to a stock exchange filing. The Noida-based company currently