Question

if local time is ahead of GMT how to calculate difference between the two

Answer 1

When it is 7 am in New York, it is 12 noon in Greenwich, because New York is west of Greenwich. For western longitudes, add the time difference to the local time. (And for eastern longitudes, subtract the time difference). We need to find the time at Greenwich (GMT) in order to calculate the chart.

India Standard Time is 5.5 hours (5 hours 30 minutes) ahead of Greenwich Mean Time(GMT+5.5).

U can easily do it on website:
greenwichmeantime



Hope it helps
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