Question

the movement of the progress bar may be uneven because questions can be worth more or less (including zero) depending on your answer. alana and petra go to a used book sale, where every book is the same price. alana buys 5 books and petra buys 4 books. they run into their friend angus, who really loves to read, and discover that he has bought 19 books. angus received a $10 discount, but he still spent $7.50 more than alana and petra combined. how much does one book cost? $0.25 $1.75 $19.75 $2.50

Explanation:

Step1: Define variable

Let \( x \) be the cost of one book (in dollars).

Step2: Calculate total books for Alana and Petra

Alana buys 5 books, Petra buys 4 books. So total books for them: \( 5 + 4 = 9 \) books. Total cost for them: \( 9x \) dollars.

Step3: Calculate Angus's cost

Angus buys 19 books, gets a $10 discount. So his cost: \( 19x - 10 \) dollars.

Step4: Set up equation

Angus spent $7.50 more than Alana and Petra combined. So:
\( 19x - 10 = 9x + 7.50 \)

Step5: Solve for \( x \)

Subtract \( 9x \) from both sides:
\( 10x - 10 = 7.50 \)

Add 10 to both sides:
\( 10x = 17.50 \)

Divide by 10:
\( x = 1.75 \)

Answer:

\$1.75 (corresponding to the option: \$1.75)