They actually left it more wealthy than they found it
India's economy was more than twice the size as the British left than it had been when they arrived. Unfortunately, it was Malthusian growth, an increase in the number of people, not an increase in living standards. As with most economic growth across history, before an industrial revolution.
www.forbes.com
The “45 Trillion” has been debunked so many times
And the wealth was concentrated to just a pocket of Elites who used it to leverage support from various European powers, tons of them allied & helped Anglos, French, Portuguese
The GDP growth that you say is not real. India was just looting it's own people.
It was stealing from it's own poor people to give to the British. In reality, this means the GDP stayed the same, and the British took all of it.
Before the Brits attacked, India was rich, and then after their arrival they were plundered, simple as that.
You are not smart, you are trying to look smart, but your argument is dumb as hell.
Pretty sure that was Mesopotamians which the Greeks improved upon
Indian mathematicians developed numbers and zero, there is even documentary evidence of it. Google up Brahmagupta.
The only thing Mesopotamia got right was their calendar, India got their calendar from them.
Zero was developed in India, and a similar concept emerged in Mesopotamia around the same time, but it is not equivalent to how we use it today.
Indians invented very advanced and simple number system, and it was way easier to remember and calculate. And it is still the same now, the numbers they use.
Mesopotanians had a base 60 number system, it was very complex.
But Indians had a base 10 number system, making it simpler.