Educated guessing & flagging

Always answer every question before time runs out. There is no penalty for a wrong answer; an unanswered question is a guaranteed zero, but a guess has a positive expected value. Never leave a blank.

With five options and no elimination, the expected value of a random guess is $\frac{1}{5}$ of a mark. With two options eliminated, it rises to $\frac{1}{3}$. Even the least informed guess is strictly better than no answer.

When to guess immediately: if a question would require more than two to three minutes to solve from scratch and you have no quick approach, make your best guess after any obvious elimination, flag the question, and move on. Return only if time allows.

The Flag for Review button marks a question for later without losing your current answer selection. Use it as soon as you sense a question will exceed your 90-second budget.

Flagging disciplines your time: knowing you'll come back removes the psychological pressure that causes candidates to keep grinding at a hard question long past the point where it's worth it. Flag without guilt; it's the correct move.

When to flag:

• You've spent ~60–90 seconds and have no clear method
• You have a method but the arithmetic will take another 60+ seconds
• You've answered but aren't confident: flag to revisit if time allows

Don't over-flag. Flagging 10 or more questions mid-module leaves an unmanageable review list at the end. Reserve flagging for genuinely unsolved or uncertain questions; questions you've answered confidently don't need it.