Math Is Fun
Math Is Fun: Compound Interest
Explains, with examples, what compound interest is and how to calculate it using a formula. Also shows how to work backwards to calculate the present value of an investment, how compound interest is calculated for different compounding...
Calculator Soup
Calculator Soup: Tip Calculator
Calculate a tip or gratuity and get the total amount to pay. Enter your meal or dinner cost along with the tip percentage. If you are splitting the cost at a restaurant among several people you can divide by the number of people to get...
University of Nebraska
Carbon 14 Dating Calendar
Provides a Carbon 14 Dating Calculator to compute the percent of Carbon 14 remaining after a given number of years. Also calculates how many years have elapsed from how much Carbon 14 remains.
Illustrative Mathematics
Illustrative Mathematics: F Le Basketball Rebounds
The purpose of this task is to introduce students to an exponential decay function in the form f(x) = abx, with a concrete interpretation of the decay factor b. A table shows the rebound height of a basketball for each successive bounce....
University of Cambridge
University of Cambridge: Nrich: The Magic Number and the Hepta Tree
Use your calculator to help you solve this challenge at this one page website. You can check your solution with only one click of the mouse.
BBC
Bbc: Percentages
You can pick up some valuable percentage pointers on how to work with them. When you finish working your way through the pages, you can take an on-line "Test Bite" and check your understanding.
OpenStax
Open Stax: Physics: Accuracy, Precision, and Significant Figures
This interactive site helps students determine the appropriate number of significant figures in both addition and subtraction, as well as multiplication and division calculations. They also calculate the percent uncertainty of a...
CK-12 Foundation
Ck 12: Uncertainty in Measurements
[Free Registration/Login may be required to access all resource tools.] In the following online lesson students will learn to distinguish between accuracy and precision in measurements and to also calculate the percent error of a...
Illustrative Mathematics
Illustrative Mathematics: F Le Carbon 14 Dating, Variation 2
In this task on exponential decay, learners calculate what the amount of Carbon 14 left in a preserved plant will be as time passes and when one microgram will be all that is left. Aligns with F-LE.A.1.c.
CK-12 Foundation
Ck 12: Chemistry Simulation: Average Atomic Mass
[Free Registration/Login Required] Students explore how percent abundances of different isotopes affect the average atomic mass for that given element. Students form connections between the average atomic mass and a person's body mass....