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Risk facts & stats

7 fact-checked facts about risk and probability, each with the reason behind it. 5 more are in today's round and join this page after it closes.

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The basics

What is the probability of rolling a 6 on one fair six-sided die?

Answer1/6

Each of the six faces is equally likely, so any one face has a 1 in 6 chance.

What is a professional who uses statistics to measure risk for insurers called?

AnswerActuary

Actuaries apply math and statistics to estimate the likelihood and cost of future events.

Going deeper

What is 'expected value' in probability?

AnswerThe average outcome over many repeats

Expected value weights each outcome by its probability, giving the long-run average.

When rolling two fair dice, which total is the most likely?

Answer7

Six of the 36 combinations add up to 7, more than any other total.

What is the probability of an event that is certain to happen?

Answer1

Probabilities run from 0 (impossible) to 1 (certain).

Expert level

How many people must be in a room for a better-than-even chance that two share a birthday?

Answer23

With 23 people the chance of a shared birthday passes 50%, the famous birthday paradox.

What is the probability of drawing an ace from a shuffled standard 52-card deck?

Answer1/13

There are 4 aces in 52 cards, and 4/52 = 1/13.

Know these cold?Today's round is five questions like these, 20 seconds each. Your streak and level follow you to every arena.Play today's round