Neutralisation and safety?

two neighbouring factories produce large quantities of effluent that they have to dispose of safely. one effluent is acidic and the other is basic 25.0 mL of one effluent required 29.5 mL 0.233 mol/L sulfuric acid for exact neutralisation 25.0 mL of the other required 32.8mL 0.274 mol/L sodium hydroxide for exact neutralisation. What volume of the first effluent should be mixed with 100 L of the second in order to produce neutral effluent?