The matrix below represents the solution to a system of equations.

As you might know from reading the Harry Potter books, wizarding money comes in three denominations: bronze Knuts, silver Sickle

Nina [5.8K]

Answer:

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

$\frac{1 galleon}{x}=\frac{17 sickles}{1 sickle}$

$x=\frac{1}{17} sickles$

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

$\frac{1/17 galleons}{x}=\frac{29 knuts}{1 knut}$

$x=\frac{1}{493} galleons$

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.

8 0

3 years ago

A shark is swimming 25 feet below the surface of the water. It goes down another 12 feet. What is the new depth the shark is swi

ivolga24 [154]

Answer:

37

Step-by-step explanation:

You add them to see the new depth

7 0

3 years ago

Consider the vectors u = <-4, 7> and v = <11, -6>. u + v = < , > ||u + v|| ≈ units

Tems11 [23]

Answer:

5 $\sqrt{2}$

Step-by-step explanation:

u + v = < - 4, 7 > + < 11, - 6 > = < - 4 + 11, 7 - 6 > = < 7, 1 >

| u + v | = $\sqrt{7^2+1^2}$ = $\sqrt{50}$ = 5 $\sqrt{2}$

6 0

3 years ago

Read 2 more answers

John took all his money from his savings account. He spent $110 on a radio and 4/11 of what was left on presents for his friend

svp [43]

Answer:

$1210

Step-by-step explanation:

Let x be total amount

First John spent $110 on a radio and 4/11 of what was left on presents for his friends so he was left with

$\frac{7}{11}(x-110)=\frac{7}{11}x-70$

Then he put 2/5 of his remaining money into a checking account

$\frac{3}{5}\left(\frac{7}{11}x-70\right)$

Rest he donated to charity

$420=\frac{3}{5}\left(\frac{7}{11}x-70\right)\\\Rightarrow \left(\frac{7}{11}x-70\right)=\frac{2100}{3}\\\Rightarrow \frac{7}{11}x-70=700\\\Rightarrow \frac{7}{11}x=770\\\Rightarrow x=1210$

Hence total amount of money John originally had was $1210

8 0

3 years ago

4.A trapezoid with a perimeter of 30 units is

Tom [10]

Answer:

It would be (x0.3,y0.3). C is the answer

Step-by-step explanation:

Because if you actually read it, it already gave you the answer which is the scale factor of 0.3

so that would lead to (x0.3,y0.3)

6 0

3 years ago