This is because India's population is incredibly large (Approximately 1.252 Billion). When compared to other countries, 12% of 1.252 billion is significant.
India has about 1225 millions of inhabitants. It is the second most populated country in the world. Although most of them are Hindus (in fact, India has most of the world's Hindus), the third largest group of Muslims live there. That would make around 147 million people that profess this religion.
That is why even though only 12 per cent of the national population is Muslim, India is still one of the world's largest Muslim populations. In the upcoming decades, it's projected India will have the largest population of Muslims and Hindus. It is expected that Muslims will grow faster than Hindus rising from 14.4% in 2010 to 18.4% in 2050.
The governments of Saudi Arabia and the United States are different because the United States is considered a democracy and Saudi Arabia is a autocracy or dictatorship.
This picture shows one of the remaining engineering features built by the ancient Romans, an aqueduct. How did the Romans use this structure? <u><em>The aqueduct, an invention of the Romans, was used to move water to communities in need. </em></u>