The On-Screen Calculator: When and How to Use It

The preceding lessons have emphasised mental arithmetic and estimation. This lesson covers the flip side: how to use the on-screen calculator effectively when you do need it. Understanding the calculator's quirks — especially the BODMAS issue — and knowing when it genuinely saves time will make you a more efficient QR candidate.

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What the Calculator Offers

The UCAT on-screen calculator has:

• Digit buttons: 0–9 and a decimal point
• Operations: +, −, ×, ÷
• Equals: =
• Memory functions: M+, M−, MR (Memory Recall), MC (Memory Clear)
• Square root: √
• Percentage: %
• Clear: C (clears current entry), CE/AC (clears everything)

It does not have:

• Brackets
• Trigonometric functions
• Logarithms
• An exponent/power button
• A backspace/undo button

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The BODMAS Problem: How the Calculator Actually Works

This is the most important thing to understand about the UCAT calculator.

Standard Mathematics (BODMAS)

In standard mathematics, the order of operations is:

1. Brackets
2. Orders (powers, roots)
3. Division and Multiplication (left to right)
4. Addition and Subtraction (left to right)