From which of the following longitude the Indian standard time is determined?
The Indian Standard Time is observed throughout India, with a time offset of UTC+5:30. This means that India is five and a half hours ahead of Greenwich Mean Time. Unlike other countries, India does not observe Daylight Saving Time. Indian Standard Time is computed on the basis of 82.5 degrees East longitude from a clock tower in Mirzapur near Allahabad, as it near the corresponding longitude reference line.