Calculating time in your head

[ESBlonde]

That's mental. Along with every other right-thinking person here, I'd take off two hours and add 13 minutes.

I'm clearly not a right thinker then. I'd add one and three quarters then plus 2 minuets. I do a bunch of time arithmetic for work and think in qtr hours.

[hungrymark]

Depends what tempo your trio is playing at, surely?

[maltingsaudio]

Depends what tempo your trio is playing at, surely?

Mornington Crescent

[Nik Harrison]

1hr 47 is close enough to 2 hours to make little difference, and builds in a safety margin. Start at 8.35. Actually start at 8.30 to build in even more safety margin since that's a bad time of day to be driving at.

+1

Although this is very much an "engineer's answer" (in a good way though)