the balanced equation for the above reaction is as follows;
2C₁₀H₂₂ + 31O₂ ---> 20CO₂ + 22H₂O
stoichiometry of C₁₀H₂₂ to CO₂ is 2:20
this means that for every 2 mol of C₁₀H₂₂ that reacts - 20 mol of CO₂ is formed
therefore when 5.0 mol of C₁₀H₂₂ reacts - 20/2 x 5.0 = 50 mol of CO₂ is formed
50 mol of CO₂ is produced.