Deduce #4: The library — the solution

The Deduce puzzle from August 18, 2026, worked through clue by clue: 7 clues, 4 rounds of crossing off, and no guessing anywhere.

The puzzle

Four people — Iris, Lena, Zara and Rosa — and three things to work out about each: their book, bag and time. The clues only ever rule things out.

1. The one with the velvet bag is exactly 3 hours after Iris.
2. Lena is the one with the plastic bag.
3. The one with the novel is not the one at 10am.
4. The one with the diary is exactly 3 hours after Iris.
5. The one with the novel is earlier than Lena.
6. The one with the songbook is not the one at 10am.
7. Rosa is the one with the tartan bag.

The walkthrough

A round is one pass over the clues. Each round applies what the last one settled; every step below is an elimination the clues force, in the order a solver would take them.

Round 1

Start with every possibility open, and take the clues in order.

Clue 1, “The one with the velvet bag is exactly 3 hours after Iris”: velvet comes off Iris; 11am, noon and 1pm come off Iris. That settles it: Iris is at 10am.

Clue 2, “Lena is the one with the plastic bag”: plastic comes off Iris, Zara and Rosa. That settles it: Lena’s bag is plastic.

Clue 4, “The one with the diary is exactly 3 hours after Iris”: diary comes off Iris.

Clue 5, “The one with the novel is earlier than Lena”: novel comes off Lena; 10am comes off Lena.

Clue 7, “Rosa is the one with the tartan bag”: tartan comes off Iris and Zara. That settles it: Iris’s bag is canvas and Rosa’s bag is tartan.

Round 2

Go back over the clues with the new facts in hand.

Canvas is Iris’s, so it comes off Zara. That settles it: Zara’s bag is velvet.

10am is Iris’s, so it comes off Zara and Rosa.

Clue 1, “The one with the velvet bag is exactly 3 hours after Iris”: 11am and noon come off Zara. That settles it: Zara is at 1pm.

Clue 3, “The one with the novel is not the one at 10am”: novel comes off Iris.

Clue 5, “The one with the novel is earlier than Lena”: novel comes off Zara; 11am comes off Lena; 1pm comes off Rosa.

Clue 6, “The one with the songbook is not the one at 10am”: songbook comes off Iris. That settles it: Iris’s book is cookbook.

Round 3

Go back over the clues with the new facts in hand.

Cookbook is Iris’s, so it comes off Lena, Zara and Rosa.

Nobody but Rosa can still have novel, so Rosa’s book is novel.

1pm is Zara’s, so it comes off Lena. That settles it: Lena is at noon.

Nobody but Rosa can still have 11am, so Rosa is at 11am.

Clue 4, “The one with the diary is exactly 3 hours after Iris”: diary comes off Lena. That settles it: Lena’s book is songbook.

Round 4

Go back over the clues with the new facts in hand.

Songbook is Lena’s, so it comes off Zara. That settles it: Zara’s book is diary.

The answer

Previous: Deduce #3 (Mon, Aug 17) · Next: Deduce #5 (Wed, Aug 19)

About Deduce

Deduce is Noggin’s daily logic grid: four people, three things to work out about each, and clues that never hand you an answer. Every puzzle has exactly one solution and can be finished by crossing off alone. How to play Deduce, or play today’s.