solve. if needed, round to the nearest hundredth (two decimal places).\n12.) a music store is advertising a…

12.

Explanation:

Step1: Calculate the discount

The discount is 25% of the regular price. The formula for finding a percentage $p$ of a number $x$ is $p\times x$. Here, $p = 0.25$ and $x=12.50$. $0.25\times12.50 = 3.125\approx3.13$

Step2: Calculate the sale - price

The sale - price is the regular price minus the discount. Let the regular price be $x = 12.50$ and the discount be $d=3.13$. $12.50 - 3.13=9.37$

Answer:

Discount: $$3.13$, Sale price: $$9.37$

14.

Explanation:

Step1: Calculate the tip amount

The tip is 20% of the cost of the dinner. Using the formula $p\times x$ where $p = 0.20$ and $x = 65.40$. $0.20\times65.40=13.08$

Step2: Calculate the total cost

The total cost is the cost of the dinner plus the tip. Let the cost of the dinner be $x = 65.40$ and the tip be $t = 13.08$. $65.40+13.08 = 78.48$

Answer:

$$78.48$

16.

Explanation:

Step1: Calculate the amount of increase

The amount of increase $\Delta x$ is the new value minus the original value. Let the original value $x_1=19000$ and the new value $x_2 = 22200$. $\Delta x=x_2 - x_1=22200 - 19000=3200$

Step2: Calculate the percent increase

The formula for percent increase is $\frac{\Delta x}{x_1}\times100%$. $\frac{3200}{19000}\times100%=\frac{320000}{19000}% \approx 16.84% \approx 17%$

Answer:

$17%$

36.

Explanation:

Step1: Calculate the decrease in price

The decrease in price is 15% of the original price. Using the formula $p\times x$ where $p = 0.15$ and $x = 0.95$. $0.15\times0.95=0.1425\approx0.14$

Step2: Calculate the new price

The new price is the original price minus the decrease. Let the original price be $x = 0.95$ and the decrease be $d = 0.14$. $0.95-0.14 = 0.81$

Answer:

Decrease in price: $$0.14$, New price: $$0.81$