From $\dfrac{4}{7} = \dfrac{t}{s}$, we get $s = \dfrac{7t}{4}$.

Since $t$ is a positive integer, different values of $t$ yield different results:

• If $t = 4$: $s = 7$ → Column A $=$ Column B (equal)
• If $t = 8$: $s = 14 > 7$ → Column A is greater
• If $t = 2$: $s = 3.5 < 7$ → Column B is greater

Since the result changes depending on $t$, the relationship cannot be determined from the information given.