Changes for 2007-8 and 2008-9 have resulted in the following rules.

“Certain symbols have a default interpretation as regards grouping, as follows.

- In the absence of grouping symbols, the
**radical sign (?)**applies to just the numeral immediately behind it by default unless the Equation-writer indicates otherwise by means of symbols of grouping. - For the
**Factorial**variation,**!**applies to just the numeral in front of it unless the Equation-writer uses grouping symbols to indicate otherwise. - For the
**Exponent**variation (Middle/Junior/Senior only), the exponent of the selected color applies to just the numeral in front of it unless grouping symbols are used. - For the
**Number of factors**and (Elementary only)**Smallest prime**variations,**x**applies just to the numeral immediately behind it by default unless grouping symbols are used. **When the default interpretations for two symbols conflict, the expression is ambiguous, and the Equation-writer must use symbols of grouping to remove the ambiguity.**

*Examples*

- The expression
**?9!**is ambiguous because the default interpretation for Factorial, which says the expression means**?(9!)**, conflicts with the default interpretation of**?**, which specifies the interpretation as**(?9)!**. - With Number of factors and Factorial,
**4+x7!**is ambiguous. The default interpretation for Factorial requires**4+x7!**to be interpreted as**4+x(7!)**. However, the default for Number of Factors requires the interpretation**4+(x7)!**Elementary: The same ambiguity applies to Smallest prime. - Middle/Junior/Senior: With Number of factors and Red Exponent,
**4+x122**is ambiguous. The # of factors default says the expression means**4+(x12)2**while the Exponent default says**4+x(122)**. - Middle/Junior/Senior: With Factorial and Red Exponent,
**?5!2**is ambiguous because the default rules clash. The**?**default requires the interpretation**(?5)!2**. However, the**!**default makes the expression**?(5!)2**, which is the same meaning required by the Exponent default.

*Note* None of the default interpretations of symbols restricts a player’s right to interpret an ungrouped Goal as he sits fit. For example, a Goal of **x4x12** with number of factors may be interpreted in two ways. If the Equation-writer wants **(x4)x12**, writing just **x4x12** is sufficient. However, the Equation-writer may also write **x(4×12)** to obtain the non-default meaning.