These squares have been made from Cuisenaire rods. Can you describe
the pattern? What would the next square look like?
Cut differently-sized square corners from a square piece of paper
to make boxes without lids. Do they all have the same volume?
Can you use this information to work out Charlie's house number?
Mrs Morgan, the class's teacher, pinned numbers onto the backs of three children: Mona, Bob and Jamie.
"Now", she said, "Those three numbers add to a special kind of number. What is it?"
Michael put his hand up.
"It's a square number", he answered.
"Correct", smiled Mrs Morgan.
"Oh!" exclaimed Mona, "The two numbers I can see also add to a square!"
"And me!" called out Bob, "The two numbers I can see add to a square too!"
"Oh dear", said Jamie disappointedly, "the two numbers I can see don't add to a square! It's either $5$ too little or $6$ too big!"
What numbers did the three children have on their backs?