Applicare la formula: $\left(a+b\right)^3$$=a^3+3a^2b+3ab^2+b^3$, dove $a=\frac{7}{5}p$, $b=\frac{5}{3}$ e $a+b=\frac{7}{5}p+\frac{5}{3}$

Applicare la formula: $\left(ab\right)^n$$=a^nb^n$

Applicare la formula: $\frac{a}{b}c$$=\frac{ca}{b}$, dove $a=49$, $b=25$, $c=5$, $a/b=\frac{49}{25}$ e $ca/b=5\cdot \left(\frac{49}{25}\right)p^2$

Applicare la formula: $\frac{a}{b}\frac{c}{f}$$=\frac{ac}{bf}$, dove $a=21$, $b=5$, $c=25$, $a/b=\frac{21}{5}$, $f=9$, $c/f=\frac{25}{9}$ e $a/bc/f=\frac{21}{5}\cdot \frac{25}{9}p$