Practical applications for uniform rates problems beyond pipes and reservoirs

[symbolipoint]

Are the simple uniform rates problems practical for anything other than for applications like inlet and outlet pipes filling or draining a reservoir? The kind I mean are the ones which immediately yield rational equations immediately upon first analysis. We find motion problems, we find job-work rate problems about people and copy machines, but many of these seem impractical, appearing to be just unnecessary ways to create exercises. The only kind of uniform rates problems which seem useful are the pipes filling or draining reservoirs. If anyone knows of applications which are not typically shown in Intermediate Algebra textbooks but are still at this level, telling about them would be very interesting.

 

[fresh_42]

Yes, those problems posed in exercises are usually very artificial. But we solve these kind of problems at their basic level all the time if we e.g. decide whether a the big box of something is cheaper than the small box, or what a few of something cost, given the price of one.

In physics we have many direct proportional quantities:
$F \sim a\, , \,U \sim R\, , \,W \sim h\, , \,C \sim Q$ etc.