Math Formula Notes

Vocabulary flashcards covering formulas for simple interest, commission, discounts, taxes, markups, and percent changes.

Simple Interest

$$I = P \times r \times t$$

Commission

$\% / 100$ then $\% \times T$

Fees

Cross $\times$, divide

Sales Price

$$\text{Sales price} = \text{Original price} - \text{discount}$$

Combined Discounts

$100 - \% = \%$ then $\text{total} \times \%$

Original Price

Cross $\times$, divide

Sales Tax

Cross $\times$, divide

Tips

Cross $\times$, divide

Markups

Cross $\times$, divide

Percent of Markup

$\text{Original} - \text{New}$, divide answer with original

Percent of Increase

$\text{Original} - \text{New}$, divide answer with original

Percent of Decrease

$\text{Original} - \text{New}$, divide answer with original

Percent Error

$\text{Original} - \text{New}$, divide answer with original