1.
If log⁡ea,log⁡eb,log⁡ec\log_e a, \log_e b, \log_e c are in an A.P. and log⁡ea−log⁡e2b,log⁡e2b−log⁡e3c,log⁡e3c−log⁡ea\log_e a - \log_e 2b, \log_e 2b - \log_e 3c, \log_e 3c - \log_e a are also in an A.P., then a+b+ca + b + c is equal to: