Everyday Guides

Everything you need to know about everyday concepts.

How to Calculate a Discount

Learn how to easily calculate percentage and fixed amount discounts for sales, shopping, and bulk purchases.

Understand the formula for calculating sales tax and how to estimate the final checkout price of your purchases.

Learn the exact mathematical method to manually calculate an exact age in years, months, and days from a birthdate.

Find out how to manually calculate the hours and minutes between a start time and an end time, including payroll conversions.

Planning a road trip? Learn the simple formula to estimate how much gas you will need and what it will cost.