I fear that even that was a little more than he could handle. What eventually worked was me saying “A little less. A little less. Take two more out. Perfect!”
It was, after all, a Friday and I didn’t want to spend my weekend teaching remedial math.
Yeah, but if you try to say that 3/4 is bigger than 1/3 because 3 > 1, what happens when you want to convince him that 1/2 is bigger than 2/5? After all, 2 > 1, too. 
That’s when you use your previous solution.
An anecdote is a short account someone tells about some event.
I knew someone would take the bait and be whooshed…
Why 2/32 of an inch for your tires, and not 1/16 ?
OK, if you say so… but I don’t get it.
Are you absolutely SURE the clock doesn’t read in decimal minutes?
I deal with this a lot at work only with hours instead of minutes. Recently I had the misfortune of trying to train one of the densest people I have ever known.
She was only expected to deal with 15 minute increments so all she had to remember was that 15 min = .25 hours. But every time it came up, she would whine and sputter and say her brain hurt from trying to figure it out.
There were only three numbers to remember and she acted like she was doing multivariable calculus.
I made the mistake of trying to help (and spare myself her querulous sniveling). I said, think of it as one dollar per hour; fifteen minutes is worth one quarter: .25 dollars.
She shot back with a snotty grunt, “Is that how you remember it?”
“No, that’s how children remember it. If I need to make a conversion I divide the number of minutes by sixty.”
I should admit at this point that doing math really did cause her physical pain and after that discussion she nearly bled out her ears.
The next day she ran into a series of calculations that had been written out using standard time keeping notation but that had used the decimal equivalent for the actual calculation. (8 1/2 hrs - 15 = 8.25)
She took a very long lunch.
So we have a QC standard measured in tenths of a minute, and a lab clock that measures minutes and seconds. At some point, one has to be converted to the other.
Wouldn’t it be a heck of a lot easier, and more accurate, to convert the standard instead of converting every single clock read-out? “OK, for this test we have to be between 15.7 and 16.2. That means between 15:42 and 16:12.”
I’ve had a number of students stare at a grade of something like 10/12 and ask with real confusion, “What kind of a grade is that?”
“Well, what’s 90% of 12?” Dumfounded look. “What’s 10% of 12?” Dumfounded look. Trying to get from that point to the point that they understand they didn’t miss 2.4 points, so it must be a B grade is more than I can usually handle.
Actually, it’s very easy.
You learned your multiplication table in grade school, right?
6x1 is 6
6x2 is 12
6x3 is 18
…and so on.
If the timer stops on a multiple of six - very easy. 6:48 is 6.8 minutes, because 48/6 is 8.
if it stops midway between a multiple - again, easy. 6:51 is midway between 6:48 and 6:54. So midway between 6.8 and 6.9. 6.85.
If it stops on either end of the midway, just round. One decimal place is good enough for my job. So 6:49? Well, it’s bigger than 6:48 (6.8) and less than the midpoint (6:51, 6.85). Just round it to 6.8.
Trust me, you do this a dozen times a day, every day (as I do) and it gets pretty quick.
Also -
A few have posted asking why we should report in decimal minutes.
Honestly, I agree with your arguments. Either we should record mm:ss or we should buy our lab techs decimal timers.
Good thing I’m not in charge :rolleyes:
Thing is, our QC techs have been using mm:ss timers for like thirty years. Recording the time has always been in decimal minutes. This is just an industry standard.
What’s so frustrating is that we’ve printed out charts for these people:
6:00 = 6.00
6:01 = 6.017
6:02 = 6.033
…etc.
Personally, I think the chart is a bit silly. The precision of the test method is probably only to within a few seconds. So whenever I record my data I just round it to the nearest tenth of a minute, as I described above.
It’s just so amazing that they work in a highly technical lab and never made the mental jump to understand the unit conversion.
/also, I can assure you nobody ever got hurt because of this awful data. Maybe some customers got pissed because their manufacturing line didn’t run as intended, but that’s the worst of it. We have some junky data that could in theory hurt our R&D.
Also, I just realized I contradicted myself
Yes, our techs are supposed to record to the second. This was in my OP.
That said, the real precision of the test is probably +/- 3 seconds.
So I think they should round to the decimal tenth of one minute, though procedure says they should round to the second.
Again, good thing I’m not in charge.
/They’ve had the seconds to decimal minutes chart for years.
Then surely at some point it would have read more than .60.
I think your concerns about customers being misled might be a bit overblown. I think anyone receiving a statement of a time period specification that was labeled “15.54” or “15:54” is generally going to assume the time base is minutes and seconds so I don’t think it’s necessarily the case that customers would be thinking 15.54 minutes is anything but minutes and seconds even if it lacked the full colon.
I can see decimalizing seconds as part a conversion equation, but as a stand alone measurement specification sent to customers it really doesn’t seem (to me) to make a whole lot of sense to be using very non-standard base ten statement of elapsed time in recording reaction times.
It’s still a stupid way to deal with it. Convert without the potential of human error, that’s what I say.
Hrm. 30 years of corrupt data. Awesome.
Shoulda had the guy give you half the 3/4ths he was trying to give you, that’s fairly close. Or you should’ve told him that 0.999…=1 and taken all you wanted when his head exploded.
There’s more of a chance of human error if you’re adding seconds than if you’re adding tenths of minutes. For example, :48 + :36. Not only might someone forget to carry the one and come up with :74 instead of :84, you then have to subtract 60 and add back the minute to come up with 1:24. It’s much easier to add .8 + .6 to get 1.4 minutes, and less prone to error.
FWIW, my logbook is in hours and tenths of hours. The Hobbs meter in the aircraft measures in hours and tenths.