In some code, letters P, Q, R, S, T represent numbers 4, 5, 10, 12, 15. It is not known which letter represents which number. If $Q-S=2S$ and $T=R+S+3$ , then what is the value of $P+R-T$ ?

Cannot be determined due to insufficient data

Kepler. Discussing PYQs. Q.no. 80

In some code, letters P, Q, R, S, T represent numbers 4, 5, 10, 12, 15. It is not known which letter represents which number. If Q−S=2SQ-S=2SQ−S=2S and T=R+S+3T=R+S+3T=R+S+3 , then what is the value of P+R−TP+R-TP+R−T ?