Gary Cottle, age 10, of Oakland, Cal  for his question:

Where was our numeral system invented?

Our neat numeral system was invented in India by the Hindus, many thousands of years ago. But for a long time, the people of Europe had no idea of this simple way of writing numbers. Until a thousand years ago, they all used the clumsy old Roman system of numerals. We still see Roman dates and other figures carved on buildings and written on documents, They are rows of letters and it usually takes time to figure out what they mean.

About 900 years ago, curtain Arab traders were traveling in India and came upon the simple Hindu system for writing numbers. They brought the idea back to Europe and, with a few changes, it is the system of numbers we use to the present day. Nowadays, almost all countries use this system, though they do not ell write the figures in the same way.