John D. Rockefeller is said to be the richest person ever to live, with an estimated wealth of $336 billion. But evidence suggests that an African named Mansa Musa probably surpassed that staggering amount. Musa lived in western Africa and became a surprisingly selfless emperor of the Mali people in 1312 A.D. By trading gold and salt, he amassed an enormous fortune, now estimated at $400 billion dollars in today's money. He is most famous for his pilgrimage to Mecca. Members of his caravan numbered some 60,000 people, and he made the journey with hundreds of animals and plenty of gold. He freely gave this gold to the poor that he met along the route. He had a number of mosques built, too. Legend has it that he built one every Friday during his reign. The most famous of these is the Djinguereber Mosque in Timbuktu, Mali.
According to the passage, how did Mansa Musa create his vast wealth?

Question

Quizplus · Accepted Answer

The author says that Mansa Musa amassed his wealth by trading gold and salt.
By going on a pilgrimage to Mecca is incorrect. Mansa Musa had already become wealthy when he set off on his pilgrimage to Mecca. 
By taxing the Mali people is incorrect. The passage says nothing about taxing the Mali people. 
By donations received at mosques is incorrect. The author says that Mansa Musa built mosques-it doesn't mention that he received donations from them.

John D Rockefeller Is Said to Be the Richest Person Ever