Before leaving to visit mexico, levant traded 270 american dollars and received. 3,000 mexican pesos. when he returned from mexico, he had 100 pesos left. how much will bee receive when he exchanges these pesos for dollars?

Before leaving to visit Mexico, Levant traded 270 American dollars to Mexican pesos and received 3 000 Mexican pesos.
=> 3 000 / 270 = 11.111… , divide this to know how much is the value of American dollars to Mexican Peso.
This means that the value of US dollars to Mexican peso is 11.11
Now, when he returned he has 100 Mexican pesos left.
=> 100 / 11.11 = 9 American dollars.
Thus, Levant has 9 American dollars left when he returned from Mexico to America.