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This was a tricky problem! Isabella from Sion Manning RC School for Girls said:
I think the squares are different colours, because the order in which squares appear on the board are - black, white, black, white etc. On either side of square B are two black squares therefore B must be a lighter square - whereas A is a darker square.She then asked ten people whether they thought the squares were the same colour or not. Here is a table of her results:
Person | Same | Different |
A | x | |
B | x | |
C | x | |
D | x | |
E | x | |
F | x | |
G | x | |
H | x | |
I | x | |
J | x |
She goes on to say:
Then she showed the same people the second picture. Here is the table of her results this time:
Person | Same | Different |
A | x | |
B | x | |
C | x | |
D | x | |
E | x | |
F | x | |
G | x | |
H | x | |
I | x | |
J | x |
Did this second survey change Isabella's mind? She wrote:
That's an interesting observation about the colour of the letters, Isabella, and I agree with you, it might well help to "trick" your eyes.
Rohaan from Longbay Primary School explained further:
Well done to all of you.