Tutorpip← About this lessonABCWith the answer keyDownload PDF
Coding · Ages 10+ · Set A
Gran's pet puzzle
Scan to mark
on screen
A
Name
Date
Start Finish
Goal: 15 min
Score/ 11
Remember: Use a clue to cross out what cannot be, and what is left must be true. A good puzzle has exactly one answer.

Read and answer

Read the story, then answer.

Whose pet is whose?Gran has a surprise for Leo, Ada and their cousin Sam. Under three covers on the porch sit a cat, a dog and a fish, and each pet belongs to one of the children. Whoosh! The wind blows the name tags away, and nobody knows whose pet is whose. Gran says there will be no peeking. They will solve it with their heads, using clues. Gran draws a grid with the children down the side and the pets across the top. A tick means yes, and a dot means no, so that pair is ruled out. Clue one says Sam's pet has no fur, and only the fish has none, so Sam has the fish. Clue two says Ada's pet does not bark, so Ada cannot have the dog, and the fish is already Sam's. That leaves the cat for Ada and the dog for Leo.
1
Clue one: Sam's pet has no fur. Which pet is Sam's?
🐈the cat🐕the dog🐟the fish
2
Clue two: Ada's pet does not bark. Which pet can Ada not have?
🐈the cat🐕the dog🐟the fish
3
Sam has the fish, so Ada cannot have the fish.
TrueFalse
4
Ada's pet does not bark, so it must be the fish.
TrueFalse
5
Sam has the fish and Ada has the cat. Whose pet is the dog?
Leo'sAda'sSam's

Another puzzle, then fix and stretch

Gran has a red, a green and a yellow hat for Leo, Ada and Sam. Clue 1: Leo's hat is not red and not yellow. Clue 2: Sam's hat is not red. Clue 3: Ada's hat is not yellow.

6
Whose hat is green?
Ada'sSam'sLeo's
7
What color is Sam's hat?
YellowRedGreen
8
Solve the hat puzzle. Put the steps in order.
  • Ada has the red hat that is left
  • Clue 2 rules out red for Sam, so Sam has yellow
  • So Leo has the green hat
  • Clue 1 rules out red and yellow for Leo
9
Join each move to what it means.
  1. 1a tick in the grid
  2. 2a dot in the grid
  3. 3only one choice left
  4. 4a good logic puzzle
  • Athat pair must match
  • Bhas exactly one answer
  • Cthat pair is ruled out
  • Dit must be true
10
Leo says: Sam has the fish, so Sam has the dog as well. What is the mix-up to fix?
Each child has one pet, so one clue does not add a second petThe fish is not Sam'sDogs do not bark
11
Clues 1 and 2 alone are enough to solve the hat puzzle.
TrueFalse
12
Write one clue for a puzzle about three people and three snacks.
13
Draw a grid for the pets, and fill in the ticks and dots for the story.
Scan the code at the top to mark this sheet on screenTake a photo of your answers or type them. It is marked for you automatically, and your score is kept.