AASA Grade 7 Ratios and Proportional Relationships. Practice it free.

The area ratio is $\dfrac{36}{4} = 9 = k^{2}\textsf{,}$ so $k = 3\textsf{.}$ Then $PQ = 5 \cdot 3 = 15\textsf{.}$

Discount: $\dfrac{50}{100} \times \text{\char36}200 = \text{\char36}100\textsf{.}$ Sale price: $\text{\char36}200 - \text{\char36}100 = \text{\char36}100\textsf{.}$

$\frac{50}{100} = 0.5 = 50\%$.

Tip $= 0.15 \times 72 = 10.80$ dollars.

Tax: $\dfrac{10}{100} \times \text{\char36}20 = \text{\char36}2\textsf{.}$

Tip: $\dfrac{18}{100} \times \text{\char36}100 = \text{\char36}18\textsf{.}$

Speed = distance $\div$ time: $\dfrac{348}{4} = 87$ miles per hour.

$\dfrac{a}{b} = \dfrac{5}{2}$. With $a = 75$, $\dfrac{75}{b} = \dfrac{5}{2}$, so $5b = 150$ and $b = 30$.