One Way Our Bodies Produce ATP Is to Couple the Formation

One way our bodies produce ATP is to couple the formation of ATP from ADP with the hydrolysis of phosphoenopyruvate (PEP) ,as shown below.
PEP + ADP + H⁺(aq) $\to$ pyruvate + ATP $~~~~~~~~$$\Delta$ _rG ^{$\circ$ '}=?

Given the following thermodynamic data,
PEP + H₂O( $\ell$ ) $\to$ pyruvate + HPO₄^2-(aq) $~~~~~~~~$$\Delta$ _rG ^{$\circ$ '} = -61.9 kJ/mol-rxn
ATP + H₂O( $\ell$ ) $\to$ ADP + HPO₄^2-(aq) + H⁺(aq) $~~~~~~~~$$\Delta$ _rG ^{$\circ$ '} = -30.5 kJ/mol-rxn
Calculate the standard Gibbs free energy of reaction for the formation of ATP from the hydrolysis of PEP.

A) 92.4 kJ/mol-rxn
B) -31.4 kJ/mol-rxn
C) -92.4 kJ/mol-rxn
D) 31.4 kJ/mol-rxn
E) -46.7 kJ/mol-rxn