Percentages — change, discount, interest
Percent change (increase and decrease), discounts, tax and tips, simple interest, percent error of measurement, and per mille.
Available exercises
Percent change (increase / decrease)
Given an old and a new value, work out the percent change.
Percent of an amount — discount, tax, tip
Work out the final price after a discount, tax or tip.
Simple interest
Given the principal, an annual rate and a number of years, compute the interest.
Percent error of a measurement
Given a measured value and the actual value, compute the percent error.