Method of successive substitution formula to obtain the solution. Method of successive substitution In modular arithmetic, the method of successive substitution is a method of solving problems of simultaneous congruences by using the definition of the congruence equation. It is commonly applied in cases where the conditions of the Chinese remainder theorem are not satisfied. There is also an unrelated numerical-analysis method of successive substitution, a randomized algorithm used for root finding, an application of fixed-point iteration. The method of successive substitution is also known as back substitution. Consider the simple set of simultaneous congruences Now, for "x" ≡ 3 (mod 4) to be
International Astronomy Olympiad International Astronomy Olympiad The International Astronomy Olympiad (IAO) is an internationally recognized annual astronomy scientific-educating event for high school students (14–18 years old), which includes an intellectual competition between these students. It is one of the International Science Olympiads. The Eurasian Astronomical Society founded the IAO in 1996. The competing part of IAO consists of three rounds: a theoretical, an observational, and a practical. Problems of the theoretical round involve classical problems in branches of astronomy, astrophysics, space and planetary physics, and maybe hypothetical situations. The observational round involves recognizing stars, constellations, estimating star magnitude and angular distance, working with