Why is Equation pronounced?
Voiced sounds are an American English default. We change most unstressed vowels to schwas to make them easier to say—they require less articulation. So we do the same thing for this T in EQUATION; we change it to an easier-to-say but very similar sound.
What is the meaning of equation?
1 : a statement of the equality of two mathematical expressions. 2 : an expression representing a chemical reaction by means of chemical symbols. equation.