A History LessonMath brain teasers require computations to solve.
When Carl Friedrich Gauss was six years old (back in 1783), his schoolteacher asked the students to add up all the numbers from 1 to 100. Unfortunately for the teacher, who was hoping to keep the class occupied, it took young Gauss only a few seconds to work out the answer. Can you figure out what Gauss did to come up with the answer?
HintThere is a pattern...
AnswerGauss realized that the series 1+2+3+4...+97+98+99+100 could be written as 1+100+2+99+3+98+4+97... or 101 times 50 to get the total 5,050.
This trick works for any sum of sequential integers. The general formula is n(n+1)/2, which is the equation for triangular numbers.
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