John Wallis
John Wallis was a smarty-pants dude who lived a loooong time ago. He liked to do maths (that's short for mathematics, which is all about numbers and stuff) and he was really good at it!
One of the clever things that John Wallis did was to figure out how to write down fractions (that's when you have one number on the top and another number on the bottom with a line between them, like 1/2) in a new and special way. He used special symbols, like two lines that look like a Roman numeral two (that's an "I" with a line on top and on the bottom) and a little "o" with a line on top like a hat. These symbols made it easy to do maths with fractions and understand them better.
John Wallis also did some other really cool things with maths. He figured out how to measure curves (like the bendy lines on a circle) using a special thing called calculus. He even used his maths skills to help build better clocks!
So, basically, John Wallis was a super-smart dude who was really good at maths and came up with new and clever ways of understanding and working with numbers.
One of the clever things that John Wallis did was to figure out how to write down fractions (that's when you have one number on the top and another number on the bottom with a line between them, like 1/2) in a new and special way. He used special symbols, like two lines that look like a Roman numeral two (that's an "I" with a line on top and on the bottom) and a little "o" with a line on top like a hat. These symbols made it easy to do maths with fractions and understand them better.
John Wallis also did some other really cool things with maths. He figured out how to measure curves (like the bendy lines on a circle) using a special thing called calculus. He even used his maths skills to help build better clocks!
So, basically, John Wallis was a super-smart dude who was really good at maths and came up with new and clever ways of understanding and working with numbers.
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