MO MAP Grade 7 Ratios and Proportional Relationships. Practice it free.

Three gallons of water is $3 \times 16 = 48$ cups. With a $7$ to $56$ ratio, $\dfrac{7}{56} = \dfrac{x}{48}$, so $56x = 336$ and $x = 6$ cups of concentrate.

Scale the ratio: $32$ oz red is $8$ groups of $4$, so blue paint = $8 \times 7 = 56$ ounces.

Cross-multiply: $9 x = 63 \cdot 6 = 378$. So $x = 42$.

Discount: $\dfrac{40}{100} \times \text{\char36}30 = \text{\char36}12\textsf{.}$ Sale price: $\text{\char36}30 - \text{\char36}12 = \text{\char36}18\textsf{.}$

Discount: $\frac{25}{100} \times \text{\char36}200 = \text{\char36}50$. Sale: $\text{\char36}200 - \text{\char36}50 = \text{\char36}150$.

Increase $= 13{,}800 - 12{,}000 = 1{,}800$. Percent increase $= \dfrac{1{,}800}{12{,}000} = 0.15 = 15\%$.

Tax: $\dfrac{10}{100} \times \text{\char36}60 = \text{\char36}6\textsf{.}$

Tip: $\dfrac{15}{100} \times \text{\char36}80 = \text{\char36}12\textsf{.}$ Total: $\text{\char36}80 + \text{\char36}12 = \text{\char36}92\textsf{.}$