Answer:
[tex]r = \frac{1}{84} c[/tex]
Step-by-step explanation:
[tex]c = 2 \times 3 \times 14r[/tex]
[tex]2 \times 3 \times 14r = 6 \times 14r = 84r[/tex]
[tex]c = 84r = 84r = c[/tex]
[tex]84r \div 84 = c \div 84[/tex]
[tex]r = c \div 84[/tex]
[tex]\boxed{\green{r = \frac{1}{84} c}}[/tex]