Numbers
How the real numbers are ordered, percentages and unit conversions: the arithmetic every other topic leans on. Numbers is tested in the Mathematics section of the Bocconi Test, which has 24 of the 50 questions (75 minutes in total, 2027/28 format). This guide covers it in 5 lessons, each with the rule that solves it and a diagram.
Number sets and the number line
ℕ ⊂ ℤ ⊂ ℚ ⊂ ℝ. A rational number is a fraction of integers, so its decimal stops or repeats; √2 and π are irrational. Compare fractions by cross-multiplying and roots by squaring.
Order and operations
Adding keeps an inequality; multiplying by a negative flips it. Reciprocals flip the order of same-sign numbers, and between 0 and 1 squaring shrinks while the square root grows.
Percentage basics
A percentage is a multiplier: +p% is ×(1 + p/100), −p% is ×(1 − p/100). Percentage change is (new − old) ÷ old, and percentage points are not percent.
Successive and reverse percentages
Successive changes multiply, so +20% then −20% is ×0.96. To undo a change, divide by its multiplier; in a mixture, hold the unchanged part fixed.
Unit conversions
Multiply by a fraction equal to 1 and cancel units. Each step is ×10 for length, ×100 for area and ×1000 for volume; km/h ÷ 3.6 = m/s.
What is the Bocconi Test format?
Online Bocconi Test for admission in academic year 2027/28, as published by Università Bocconi.
- Questions / time
- 50 / 75 minutes
- Distribution
- 24 mathematics · 11 reading · 6 numerical reasoning · 9 critical thinking
- Scoring
- +1 correct · 0 blank · −0.2 wrong
- Question languages
- English · Italian
- Three-option questions
- Some critical thinking questions have three options; a wrong answer there costs −0.33
- Minimum score
- Below 17 points the test is not considered for selection
- AI degree
- Mathematical and Computing Sciences for Artificial Intelligence also needs at least 11 of 24 points in mathematics
- Law test
- A separate test, 50 questions / 75 minutes: 5 mathematics · 11 reading · 6 numerical reasoning · 18 logic and critical thinking · 10 verbal reasoning; same scoring
Source: Università Bocconi, Online Bocconi Test page (checked October 7, 2026)
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