Four divided by four plus one equals three.

For example:

4+5=9

5+4=9

9-5=4

9-4=5

Extended data:

In mathematics, formula refers to the formula listed in the calculation of numbers (or algebraic expressions), including numbers (or letters instead of numbers) and operation symbols (four operations, power, root, factorial, permutation and combination, etc. ) and "=". According to the different calculation methods, the formulas are generally divided into horizontal and vertical.

Unlike expressions, expressions are expressions that connect data of the same type (such as constants, variables, functions, etc.). ) Use operation symbols according to certain rules. Expressions are expressions that connect numbers through operation symbols to calculate results, and need an equal sign.

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