Question

why did gmt is international time

Answer 1

GMT is the reference time for girls time zone

Answer 2

A single time zone setting the baseline for the rest of the world was first proposed in 1876 when the engineer and inventor Sandford Fleming called for a global 24-hour clock.
Then,after few years,as U K grew into an advanced maritime nation, mariners kept at least one chronometer (a device for measuring time) on GMT to calculate their longitude from the Greenwich meridian, which was by convention considered to have longitude zero degrees,...

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