One Wasn't Square

Mrs Morgan, the class's teacher, pinned numbers onto the backs of three children. Use the information to find out what the three numbers were.
Exploring and noticing Working systematically Conjecturing and generalising Visualising and representing Reasoning, convincing and proving
Being curious Being resourceful Being resilient Being collaborative

 

Mrs Morgan, the class teacher, pinned numbers onto the backs of three children: Mona, Bob and Jamie.

 

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One Wasn't Square

"Now," she said, "Those three numbers add to a special kind of number. What is it?"

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One Wasn't Square

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?