Reading tables: the frame first, then the figures

Where tables sit in the test

Data insight is 16 of the test's 50 questions. Bocconi describes two kinds of item in it: numerical critical reasoning, where tables, histograms, graphs or short passages are followed by several questions, and data sufficiency, which has its own two lessons at the end of this unit. This lesson and the next five are about the first kind, starting with the plainest display of all, the table.

Two rules of the test shape how you should work. Calculators are not allowed, but you may have a pen and two blank A4 sheets. And because several questions are built on the same display, a minute spent understanding the table once is repaid on every question that follows it.

Read the frame before the numbers

Before you look at a single figure, read four things:

1. The title and any note. They give the period, the population and sometimes a definition. "Revenue, thousands of euros, 2025" tells you that 150 means €150,000 and that every figure is for one year.
2. The units of each column. Counts, euros, percentages and rates behave differently. A column of percentages cannot be added across rows; a column of counts can.
3. What one row is. A shop, a month, a product, a region. A question about "the shops" means the shop rows only.
4. Total rows and columns. A line labelled "Total" or "All" is not one more category. It is the sum of the others, and it is the most common source of miscounts when a question asks "how many shops…".

Most wrong answers on tables come from the right method applied to the wrong row or column, not from bad arithmetic.

Match the question to an operation

Once the frame is clear, decide what the question needs before touching the numbers.

The question asks for	What you do
A value, the largest, the smallest	Read one cell, or scan one column
"How many rows satisfy…"	Test each row against the condition, one at a time
A difference ("how much more")	Subtract two cells with the same units
A share, a proportion, "what fraction of"	Divide a part by its own whole
A comparison of shares across rows	Compare fractions without fully dividing

A share needs the right whole. "What share of Arco's annual revenue came in the fourth quarter" divides by Arco's annual total, not by all shops' fourth-quarter revenue. Say the whole aloud before dividing.

Comparing fractions without a calculator

Questions often ask which row has the largest share, and the fractions will not be friendly. Three tools cover nearly every case.

• Benchmarks. Know $\frac{1}{8} = 12.5\%$, $\frac{1}{6} \approx 16.7\%$, $\frac{1}{5} = 20\%$, $\frac{1}{4} = 25\%$, $\frac{1}{3} \approx 33.3\%$, $\frac{3}{8} = 37.5\%$. Many fractions sit clearly above or below one of them: $\frac{140}{440}$ is less than $\frac{1}{3}$ because $3 \times 140 = 420 < 440$.
• Simplify first. $\frac{135}{360}$ looks awkward, but dividing both by 45 gives $\frac{3}{8}$.
• Cross-multiply. To compare $\frac{a}{b}$ with $\frac{c}{d}$ (all positive), compare $a \times d$ with $c \times b$. The larger product goes with the larger fraction, and you never divide.

You rarely need a share to two decimal places. You need to know which is bigger, or whether it passes a threshold.

Strict and non-strict conditions

"More than", "at least", "fewer than" and "no more than" decide what happens to a tie. If a row has exactly the threshold value, "more than" excludes it and "at least" includes it. Questions about tables like to put one row exactly on the line, so mark ties as you scan.

A routine for every table

Read the frame. Restate the question as "which cells, which operation". Work on the A4 sheet, writing down the few numbers you use, so a slip can be found. Then glance back: does the answer have the right units and a sensible size?