Applicare la formula: $x,\:a,\:b$$=eval\left(x,a,b\right)$, dove $a=p=5$, $b=q=5$, $x=\frac{4}{5}pq$ e $x;a=\frac{4}{5}pq,\:p=5,\:q=5$

Applicare la formula: $ab$$=ab$, dove $ab=5\cdot 5\left(\frac{4}{5}\right)$, $a=5$ e $b=5$

Applicare la formula: $\frac{a}{b}c$$=\frac{ca}{b}$, dove $a=4$, $b=5$, $c=25$, $a/b=\frac{4}{5}$ e $ca/b=25\left(\frac{4}{5}\right)$

Applicare la formula: $ab$$=ab$, dove $ab=25\cdot 4$, $a=25$ e $b=4$

Applicare la formula: $\frac{a}{b}$$=\frac{a}{b}$, dove $a=100$, $b=5$ e $a/b=\frac{100}{5}$