Speed = 225 metres per minute
Distance = 15 km = 15,000 metres
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s=d/t
ts=d
Therefore: t=d/s
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Time = Distance / Speed
Time = (15,000 metres) / (225 metres per minute)
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Let's work it out:
[tex]Time=\frac { 15,000\quad metres }{ \frac { 225\quad metres }{ 1\quad minute\left( s \right) } } \\ \\ =\frac { 15,000\quad metres }{ 1 } \cdot \frac { 1\quad minute\left( s \right) }{ 225\quad metres } \\ \\ =\frac { 15,000 }{ 225 } minutes[/tex]
[tex]\\ \\ =\frac { 200 }{ 3 } minutes\\ \\ \frac { 200 }{ 3 } minutes\quad =\quad 66\quad minutes,\quad 40\quad seconds[/tex]
