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210$\times$190 | 198$\times$202 | 200$\times$200 |
195$\times$205 | 186$\times$214 |
A 2-Digit number is squared. When this 2-digit number is reversed and squared, the difference between the squares is also a square. What is the 2-digit number?
The squares of any 8 consecutive numbers can be arranged into two sets of four numbers with the same sum. True of false?
Can you explain the surprising results Jo found when she calculated the difference between square numbers?