Hallo anonymous !
400 ⇒ 100%
x ⇒ 30%
x / 400 = 30% / 100% Das ist eine Verhältnisgleichung
x / 400 = 30 / 100 [ * 400
x = 400 * 30 / 100
x = 120
30% von 400 sind 120
Gruß asinus :- )
$${\mathtt{G}} = {\frac{{\mathtt{P}}{\mathtt{\,\times\,}}{\mathtt{100}}}{{\mathtt{p}}}}$$ $${\mathtt{P}} = {\frac{{\mathtt{G}}{\mathtt{\,\times\,}}{\mathtt{p}}}{{\mathtt{100}}}}$$ $${\mathtt{p}} = {\frac{{\mathtt{P}}{\mathtt{\,\times\,}}{\mathtt{100}}}{{\mathtt{G}}}}$$