Education Guides
College costs compound. Calculate before you commit.
These guides model the full cost, loan burden, and ROI of education decisions so you can choose wisely rather than just applying everywhere and hoping.
How Long Will Student Loans Follow You?
A $35,000 loan on standard repayment costs $13,000 in interest. On 25-year income-driven repayment, you might pay $40,000 in interest. The difference between paths is measured in years and tens of thousands of dollars.
Can You Afford College?
The sticker price is not what most students pay. Here is how to calculate your actual net cost, the debt load you are taking on, and whether the investment makes financial sense.
What Is Your GPA — and What Grades Do You Actually Need?
Recovery is always slower than the fall. Here is the math behind GPA, why it changes less than you expect, and how to calculate exactly what you need.
What Grade Do You Need on the Final?
This is not a mystery — it is weighted average math. Here is how to calculate your current standing and find exactly what you need on the final before you sit down to study.
What Is the Average, Middle, and Most Common Value?
Statistics has three different averages because no single definition works best for all data. Here is when each is appropriate — and when using the wrong one misleads.
How Many People Do You Need to Survey?
A survey of 1,067 people provides plus or minus 3% accuracy at 95% confidence whether the population is 100,000 or 300 million. Here is why — and how to calculate the number you actually need.
Binary and Hex: Understanding Number Bases
Everything a computer stores is binary. But humans rarely read binary directly — which is why hex and octal exist. Here is how all four bases connect.
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