Originally, each country had its own, and rather poorly reproducible, unit of luminous intensity; it was necessary to wait until 1909 to see a beginning of unification on the international level, when ... Continue reading
What 3 dimensional shape will pass through a rectangle, triangle and circle each time filling the whole space? The answer may surprise you in it's simplicity. Before I tell you what it is, see if you ... Continue reading
Many concepts that we all take for granted sounded strange and foreign when first introduced. Take the number zero for instance. Any first-grader can recognize and use zeros. They sound so logical and ... Continue reading
A prime number is a number that is divisible only by one and by itself. Factors are numbers that can be divided into a number with no remainder. The factors of 18 are the numbers 1, 2, 3, 6, 9, and ... Continue reading
