Let +a+ = number of trumpet players Let +b+ = number of saxophone players --------------------- (1) +a+=+b+-+10+ (2) +b+=+3a+ ---------------- Substitute (2) into (1) (1) +a+=+3a+-+10+ (1) +2a+=+10+ (1) +a+=+5+ and (2) +b+=+3%2A5+ (2) +b+=+15+ ------------------ There are 5 trumpet players and 15 saxophone players