We received several very detailed solutions to this problem - thank you. You might have noticed that, like in real life, even if you kept the training regime the same, the rowers' time trials did vary slightly so this means you won't all have found exactly the same optimum training regime.

Sarah and Lauren, and Laura and Emily, and Elle and Danielle, all from St. Mary's C.E. Primary Albrighton, used a spreadsheet to keep track of the trials. Here are Laura and Emily's results:

 Test Circuit (minutes) Running (miles) Rowing (hours) Time (seconds) 1 0 0 0 29.00 2 1 1 1 29.00 3 2 2 2 28.50 4 3 3 3 28.25 5 4 4 4 27.75 6 5 5 5 27.50 7 6 6 6 27.75 8 7 7 7 28.00 9 8 8 8 28.25 10 9 9 9 28.50 11 10 10 10 28.75 12 25 11 4 25.75 13 30 8 4 24.75 14 35 8 4 25.85 15 30 11 6 26.55 16 30 11 5 25.65

I wonder what made you jump from the values in test 11 to test 12? Perhaps you were listening to what your other classmates had tried too? So, the best time that they got was 24.75s when the training included 30 minutes of circuits, 8 miles running and 4 hours of rowing.

Sam, Alex and Ryan from Brewood Middle School also used a spreadsheet, which you can see here . They say:

First we tried a score which seemed the best we could think of then we changed one thing at a time to see which was best for each.

Their suggested regime is 19 minutes of circuits, 10 miles of running and 5 hours of rowing which gave a time of 25 seconds.

Yasmin from Rochester Grammar School told us:

Per day: 21 minutes of circuit training 10 miles running 4 hours of rowing
I found this out by seeing how long it would take the rowers in a time trial if they did not do any training. I then tested each type of training in turn to find out the best. I found that the best type was running at 10 miles a day and then experimented with other types of training until I came to 20, 10, 4. I then added one at a time and subtracted one at a time until I came to 21, 10, 4. To check my solution, I tried various combinations but this is the best one I have been able to find so far.

Yasmin also sent this spreadsheet which shows the combinations she tried.