Question

if it takes 15 min to travel 25km , how long will it take to travel 40 km at the same rate

Answer 1

24 minutes.

\[\frac{ 15 mins }{ 25km }=\frac{ x }{ 40km }\]
We want to find the value of x, which represents how long (in minutes) it will take to travel 40 km.
So, we need to "cross multiply";

Answer 2

\[15\times40=600\]
\[25\times x=25x\]
So,
\[600=25x\]
Now we need to divide by 25 to get x alone;
\[\frac{ 600 }{ 25 }=\frac{ 25x }{ 25 }\]
\[24=x\]