Need help Figuring what formula to use.

Question

Castle took a trip to Poland. Upon leaving he decided to convert all of his Zlotych back into dollars. How many dollars did he receive if he exchanged 54 Zlotych at a rate of $6 to 18 Zlotych. Round your answer to the nearest whole number. 

 

Thank You.

Answer 1

The currency of Poland is the Zloty.

 

6 : 18 :: d : 54               proportion

18d = 324                     product means/extremes

d = 18

 

Or

 

54 is three times 18 so the dollar amount would be three times $6, or $18.

Answer 2

This is a ratio problem. Set up the ratio using $6 to 18Z.

 

$6/18Z = X/54Z Cross multiply

 

$6 * 54Z = 18XZ

 

$324Z = 18XZ Divide both sides by 18Z to solve for X

 

$324Z/18Z = 18XZ/18Z

 

$18 = X