Question

why did British blended all India wealth

Answer 1

If British not sucked out wealth from India, India would have been where Britian is today. $45 trillion is what Britain looted from India.

Answer 2

Babar, the first Mughal emperor, wrote an autobiography, the Babar-Nama. He did not much like India. It was too hot and he longed for the fruits and the mountains around Ferghana, where he grew up, in Central Asia. The best thing about India, he said, was that there was a lot of gold. Even now, it is widely believed that at least 1/4 of the gold ever mined is to be found adorning Indian women, or buried under the floors of their bedrooms. For over two thousand years India was the natural home of money, like New York and London are now. The ancient Roman Empire was forced to continuously devalue its silver currency, the denarius, because the money flowed to India. Why?

The ability of any pre-industrial country to pay taxes to its rulers, in order to fund the government, the military, public works, and so on, depends on the amount of agricultural land and, crucially on the yield of the land. All else being equal the size of the economy is proportionate to the agricultural resources and the population; but if in one country it takes five farmers to support one soldier, or one priest, or one factory worker, and in a second country the ratio is one to one then the second country is five times richer than the first. So it is not surprising that, as reported by Sanket Padekar, who also answered this question, the revenues of the emperor Aurenzeb exceeded those of any European monarch by an order of magnitude; India's population, after all, was at least as large as that of Europe, and probably significantly larger.

India has a huge agricultural potential. Even now, with 1.3 billion people, there remains a lot of unused potential. In the past, only the richest lands, with secure water supply, were worked. And the average yield was excellent. There are many records of cultivators in the best districts paying a third or more of their harvest to the zamindar or jagirdar (who paid land tax out of that) and still living quite well off the rest. No wonder the tax yield to the rulers was so high.