16.4.2 Numeric expressions

expr supports the usual numeric operators, in order of increasing precedence. The string operators (previous section) have lower precedence, the connectives (next section) have higher.

`+ -'

Addition and subtraction. Both arguments are converted to numbers; an error occurs if this cannot be done.

`* / %'

Multiplication, division, remainder. Both arguments are converted to numbers; an error occurs if this cannot be done.