Answer:
b
Step-by-step explanation:
given [tex]\frac{m}{a}[/tex] = [tex]\frac{b}{r}[/tex]
(a) is true
consider the numerical example
[tex]\frac{3}{2}[/tex] = [tex]\frac{6}{4}[/tex] ⇔ [tex]\frac{2}{3}[/tex] = [tex]\frac{4}{6}[/tex]
(b) is not true ( cross- multiply the original equation ) gives
mr = ab ⇒ (c) is true
(d) is true
using result from (c) divide both sides by a and m
[tex]\frac{mr}{am}[/tex] = [tex]\frac{ab}{am}[/tex] ⇒ [tex]\frac{r}{a}[/tex] = [tex]\frac{b}{m}[/tex]
