Do lawyers need maths? Skills and worked examples

Lawyers need practical numeracy: the ability to understand figures, select the right calculation and check whether the result makes sense. That is different from saying that every lawyer needs advanced mathematics or that every law degree has the same maths entry requirements.

If numbers make you nervous, focus on the tasks you can practise. Percentages, proportions, time-based charges and simple interest are useful starting points. The legal work often lies in deciding which figures and assumptions belong in the calculation.

Do you need maths to study law?

Check the published requirements for each course you are considering, including GCSE or equivalent requirements and any combined-degree conditions. Do not infer an admissions rule from the general description of law as an essay-based subject.

You may also encounter more numerical work in some modules than others. Business law, tax and solicitors’ accounts require careful handling of figures; interpreting evidence or a damages problem can require numeracy too. Your syllabus tells you what you are expected to do.

The SRA’s SQE1 assessment specification is the starting point for SQE coverage. Always use the specification and rules applicable to your sitting.

What numerical skills are useful?

Start with four habits:

• Identify the units: pounds, days, hours, shares or percentages.
• Write the method before entering figures into a calculator.
• Estimate the likely size of the answer.
• Check the result against the question and round only when appropriate.

The examples below are hypothetical arithmetic exercises. Their percentages and rates are supplied assumptions, not statements of a tax rate, court award or contractual entitlement.

Example 1: calculate a percentage reduction

Question: An exercise gives an initial amount of £18,000 and directs you to reduce it by 15%. What remains?

The reduction is £18,000 × 0.15 = £2,700. The remaining amount is £18,000 − £2,700 = £15,300.

Check the direction of the calculation. If the question asks for the reduction, the answer is £2,700; if it asks for the amount remaining, it is £15,300. Both numbers can appear among plausible MCQ options.

You can cross-check the result by calculating 85% of £18,000. Before doing either calculation, estimate: a 15% reduction should leave substantially more than half the original sum.

Example 2: distinguish simple interest from compound interest

Question: Assume a contract provides simple interest at 6% per year on £12,000 for exactly nine months, with the year divided into twelve equal months. How much interest is due under those assumptions?

Use principal × annual rate × fraction of a year:

£12,000 × 0.06 × 9/12 = £540.

The total principal plus interest is £12,540. Do not charge a full year’s interest or compound it when the question specifies simple interest.

In a real problem, first check the legal or contractual basis, the applicable rate, dates, day-count method and whether interest is simple or compound. Arithmetic cannot supply a missing entitlement or assumption.

Example 3: convert minutes into a fee calculation

Question: A training exercise states an hourly rate of £180 and 35 minutes of chargeable work. Assume exact pro-rata billing, with no rounding, tax or additional charge. What is the fee?

Thirty-five minutes is 35/60 of an hour, not 0.35 hours.

£180 × 35/60 = £105.

A useful check is that half an hour would cost £90 and an hour £180, so £105 is plausible. The question expressly removes billing increments and additional charges; do not import them from a different example.

Example 4: distinguish a percentage from percentage points

If a holding changes from 20% to 25%, it increases by 5 percentage points. Relative to the original 20%, the increase is 25%, because 5 ÷ 20 = 0.25.

Those statements describe different comparisons. In a problem involving shares or voting proportions, make clear which comparison you are making before choosing an answer.

How can you improve without becoming a maths specialist?

Keep a short list of recurring mistakes: treating minutes as decimals, applying a percentage to the wrong base, confusing interest with the total debt or rounding too early.

Practise one type of calculation at a time, then mix the types. Explain your method in a sentence. If you cannot explain why you used a particular percentage or time period, revisit the question before trusting the calculator.

If numeracy is creating a persistent barrier, use your provider’s academic-skills support and discuss any relevant assessment adjustments. Practise with the calculator or tools permitted for your assessment.

Connect the calculation to the law

Law Answered+ gives you access to all our revision guides and casebooks covering the full syllabus, with MCQ Master included. One revision membership brings together the explanations, authorities and practice questions you can use across your subjects. Start with the relevant guide to understand the legal framework before attempting questions involving figures.

MCQ Master includes business, tax and solicitors’ accounts topics. It is a law question bank, so use it to practise applying the relevant rules alongside your calculation skills. A correct number matters most when it answers the legal question you were actually asked.