Answer:
25 km
Step-by-step explanation:
[tex]\text{We know:}\\\\v=\dfrac{s}{t}\\\\v-speed\\s-distance\\t-time\\\\\text{We have}\ v=20\ \frac{km}{h}\ \text{and}\ t=1\dfrac{1}{4}h=\dfrac{5}{4}h.\\\\\text{Substitute:}\\\\20=\dfrac{s}{\frac{5}{4}}\\\\20=s\cdot\dfrac{4}{5}\qquad\text{multiply both sides by 5}\\\\100=4s\qquad\text{divide both sides by 4}\\\\25=s\to s=25\ km[/tex]
