As you might know from reading the harry potter books, wizarding money comes in three denominations: bronze knuts, silver sickles, and golden galleons. 29 knuts make up one sickle, and there are 17 sickles in a galleon. you can also assume that 1 galleon is worth $7.35. you are at gringotts, exchanging your money. what is the minimum amount of dollars you would need to exchange to purchase the fantastic beasts and where to find them by newt scamander? the book costs 12 galleons, 16 sickles, and 25 knuts.

Minimun amount = $95,48

Step-by-step explanation:

We need to buy the book that costs 12 galleons, 16 sickles, 25 knuts.

At the bank we need to exchange our dollars. We know that:

1 galleon = $7,35

And:

1 galleon = 17 sickles

1 sickle = 29 knuts

First we use a rule of three to convert everything to galleons:

1 galleon = 17 sickles ⇒ 1 sickle = 1/17 galleons

1 sickle = 1/17 galleons = 29 knuts ⇒ 1 knut = 1/493

And now we need to convert every wizarding money to dollars by using our reference above:

1 galleon = $7,35

1 sickle = 1/17 galleons = $7,35 / 17 ≅ $0,4323

1 knut = 1/493 galleons = $7,35 / 493 ≅ $0,0149

Finally we calculate the cost of the book:

Galleons: 12 x $7,35 = $88,2

Sickles: 16 x $0,4323 = $6,91

Knuts: 25 x $0,0149 = $0,37

Cost of the book = $88,2 + $6,91 + $0,37 = $95,48

So this is the minimun amount of dollars you need to exchange to purchase the book.

thats not a system of equations, that is a solution