Two pages, two goals
This page is about the calculator. It shows which buttons to press to compute fractions, squares, and roots on the GED calculator. If you want to memorize and recognize the common squares, cubes, and roots without a calculator, go to Squares, Square Roots, Cubes & Cube Roots.
🧠 Squares, Cubes & Roots →
📖 The Lesson
The GED gives you a TI-30XS calculator for most of the math section. Most students know how to add, subtract, multiply, and divide on it — but a handful of buttons get ignored entirely. Those are exactly the ones this lesson covers. Master these and you'll stop leaving points on the table.
The main point: The GED tests fractions and powers constantly. Entering them by hand and doing the arithmetic in your head is slow and error-prone. The calculator handles all of it — you just need to know which buttons to press.
Part 1 — The Fraction Button
Use \(\frac{n}{d}\) to enter any fraction.
The \(\frac{n}{d}\) button lets you enter fractions directly. Press the numerator first, then \(\frac{n}{d}\), then the denominator. The calculator displays it as a stacked fraction and treats it exactly like a fraction in all calculations.
Example — entering \(\frac{3}{4}\):
Press 3 \(\frac{n}{d}\) 4 and the display shows \(\frac{3}{4}\).
Example — adding \(\frac{1}{3}\) + \(\frac{1}{4}\):
Press 1 \(\frac{n}{d}\) 3 + 1 \(\frac{n}{d}\) 4 =
The calculator returns \(\frac{7}{12}\) — already in lowest terms. No common denominator work required.
Part 2 — The Conversion Button
Use ◄ ► to switch between fraction and decimal.
After you enter a fraction or get a fraction as a result, press ◄ ► to toggle between the fraction and its decimal equivalent. This is useful when an answer choice is a decimal but your calculator is showing a fraction — or vice versa.
Example:
Enter 3 \(\frac{n}{d}\) 4, then press ◄ ►
Display switches from \(\frac{3}{4}\) to 0.75
Press ◄ ► again and it flips back to \(\frac{3}{4}\). Use this any time you need to match the format of an answer choice.
Here are the power and root buttons. These show up constantly in geometry — area of squares, right triangles, and the Pythagorean theorem.
Square — x²
Number, then x²
Enter the number first, then press x².
5² = 25:
Press 5 x² = → 25
\(\frac{2}{5}\)² = \(\frac{4}{25}\):
Press 2 \(\frac{n}{d}\) 5 x² = → \(\frac{4}{25}\)
Square Root — √
2nd then x²
Square root is the second function on the x² key. Press 2nd first, then x², then the number.
√49 = 7:
Press 2nd x² 4 9 = → 7
√2 ≈ 1.41:
Same steps → 1.4142…
Cube — x³
Number, then ^ 3
There's no dedicated cube button. Use the caret ^ (exponent key) with 3.
4³ = 64:
Press 4 ^ 3 = → 64
This works for any exponent — just change the 3 to whatever power you need.
Cube Root — ∛
3 then 2nd then ^ then number
Enter the index 3 first, then press 2nd, then the ^ key, then the number under the radical, then ENTER.
∛125 = 5:
Press 3 2nd ^ 1 2 5 ENTER → 5
∛8 = 2:
Press 3 2nd ^ 8 ENTER → 2
To get a decimal result:
After pressing ENTER, press ◄ ► then ENTER again to convert.
| What you want |
Keystrokes |
Example |
| Enter a fraction |
n \(\frac{n}{d}\) d |
\(\frac{3}{4}\) → 3 \(\frac{n}{d}\) 4 |
| Convert fraction ↔ decimal |
◄ ► |
\(\frac{1}{2}\) ↔ 0.5 |
| Square a number |
n x² |
6² → 6 x² = 36 |
| Square root |
2nd x² n |
√81 → 9 |
| Cube a number |
n ^ 3 |
3³ → 3 ^ 3 = 27 |
| Cube root |
3 2nd ^ n ENTER |
∛64 → 3 2nd ^ 6 4 ENTER = 4 |
The takeaway: You don't need to memorize square roots or cube roots — the calculator handles them. What you do need to know is which buttons to press. Practice entering a few fractions like \(\frac{2}{5}\) and \(\frac{7}{10}\) until it feels automatic, and get comfortable using ◄ ► to switch formats.
🔢 Worked Examples
Example 1 — Fraction addition
Simplify: ½ + ¼
Press: 1 [n/d] 2 [+] 1 [n/d] 4 [=]
Calculator shows: 3/4
Answer: 3/4
Example 2 — Square and square root
The area of a square is 144 cm². What is the side length?
A = s²
144 = s²
s = √144
Press: [2nd] [x²] 1 4 4 [=]
s = 12 cm
Example 3 — Cube root
A cube has a volume of 216 cm³. What is the side length?
V = s³
216 = s³
s = ³√216
Press: 3 [2nd] [^] 2 1 6 [ENTER]
s = 6 cm
Reference
GED Formula Sheet
All formulas available on the real test — opens in a new tab
📋 Open Formula Sheet
✏️ Practice Questions
Up Next in GED Tools and Foundations
Negative Numbers
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