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Free sample · Sec 1

Date logic — eliminate, then conclude

eliminating dates step by step until one possibility remains.

Reasoning sample with original dates — not an Olympiad scrape.

Sec 1 · Algebra · Sec 1 · Angles · A-Math sample

I Do

Worked example

Asha’s picnic is on exactly one of these dates: 7 Apr, 12 Apr, 7 May, 15 May, 12 Jun, 15 Jun.

Reasoning sample with original dates — not an Olympiad scrape.

Eliminate the month

Clue 1: The picnic is not in April. Cross out 7 Apr and 12 Apr.

Left: 7 May, 15 May, 12 Jun, 15 Jun.

Eliminate the day

Clue 2: The day is not the . Cross out 7 May.

Left: 15 May, 12 Jun, 15 Jun.

Eliminate again — conclude

Clue 3: The month is not June. Cross out 12 Jun and 15 Jun.

Only 15 May remains. So Asha’s picnic is on 15 May.

Move: eliminate month then eliminate day then eliminate month. Why: each clue removes a whole group until one date is left.

We Do

Try this step

After Clue 1 (not April), the list is 7 May, 15 May, 12 Jun, 15 Jun. Clue 2 says the day is not the . Which dates remain?

You Do

On your own

From 15 May, 12 Jun, 15 Jun, Clue 3 says the month is not June. What is Asha’s picnic date?

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