Comments on: When Will My Cousin Graduate?

By: Dan Meyer

Dan Meyer — Tue, 07 Jul 2015 01:17:03 +0000

Many congrats to Scott & Kyle Pearce for having the closest calculations. Recap posted now.

By: dy/dan » Blog Archive » Graduation & What It Means To “Model With Mathematics”

Tue, 07 Jul 2015 00:06:08 +0000

[…] times with a linear equation. (“Time v. names read” was my model, though commenter Josh thinks “time v. number of syllables read” would be more accurate.) The calculation for […]

By: Dan Meyer

Dan Meyer — Sat, 04 Jul 2015 02:50:10 +0000

Heh. Strong play, there. Answer coming on Monday. Happy fourth everybody, if US holidays are your thing.

By: aga bey

aga bey — Fri, 03 Jul 2015 20:23:46 +0000

16.3 minutes.
I took the average of all submissions upthread

By: Scott Miller

Scott Miller — Thu, 02 Jul 2015 01:29:10 +0000

I recorded when each graduate handed his or her name card to the reader by stopping the video. Using Desmos I plotted the graduate number versus time after converting the minutes into seconds. After running a linear regression I came up with your cousin being the 157th graduate handing his card to be read at the 16:05 mark. Ardash’s name would be read a second or two after that, say 16:07. You would probably want to set your timer a little earlier so you are fully awake when your cousin’s name is called.

Several assumptions are made in the problem solving. (1) The same name reader is used throughout the graduation. (2) The name reader keeps the same pace. (3) There is no mix up that delays the name reading.

Terrific problem to engage students with.

Here is the link to Graduation Nap https://www.desmos.com/calculator/bljygbqwoa

By: Chuck Collins

Chuck Collins — Wed, 01 Jul 2015 19:44:28 +0000

A solution and an observation.

We all agree that we have some pretty noisy data (exactly how many names per minute? and will it be the same the whole time?), so instead of going for the golden ‘one answer’, let’s look at various possible answers. Using @Megan’s data, we have either 9, 10 or 11 names per minute and 156 total people, so we can come up with 3 answers:

9/minute gives 156/9 = 17’33”
10/minute gives 156/10 = 15’36”
11/minute gives 156/11 = 14’10”
(add 15″ for the video time)

Now we can go back to the conditions that Dan has set (1) he need’s to take a nap (so we should maximize his sleep time) and (2) he doesn’t want to miss his cousin’s trip across the stage (so close but over is not good). So you might say, to be safe, take the shortest time: 14’25” on the video. But what if the reader does speed up? Maybe we should look at the results for 12/minute or 13/minute. If Dan absolutely can’t miss, then we might say ‘no nap’, but Dan just finished his PhD so sleep is very valuable, so maybe we’ll allow a 10% chance that he misses the walk just so he can get some extra winks in, and pick something in the middle like 15’51”.

The (long) point is that although “math is great because it only has the once correct answer” (usual reason why a student likes math), when you get ‘real’ and use some data, it no longer makes sense to say that we have the one answer.

(If we had the time and patience, we could produce a time for each person, and look at the possible distributions of overall time with some assumptions about the distribution of times/names, and produce a more complex model, but we’d still end up with what should be a fuzzy answer)

By: Craig

Craig — Wed, 01 Jul 2015 14:06:51 +0000

This method definitely took longer than some of the other estimates. I’m not sure how much nap time you would have left. I created a table in Desmos that used the graduate number as the x-variable and the time in seconds when the graduate’s card was handed to the speaker as the y-variable. I recorded all 33 graduates in the video. Then I used the linear regression tool, assuming the name reading will continue at a semi-constant rate. I was given a slope of 6.1788 and a y-intercept of 12.597. I counted Adarsh as the 156th graduate. Therefore, I guess Adarsh graduates 16 minutes and 16 seconds into the name reading.

Here is a link to my table/graph:

https://www.desmos.com/calculator/dge8legbsn

By: Megan Schmidt

Megan Schmidt — Mon, 29 Jun 2015 21:33:49 +0000

I watched the 3:30 video about three times and came up with about 11 people in the first minute, 9 in the second and 10 in the third. Using approximately 10 people per minute I broke the group down into groups of 10 people. I got 15 groups with 6 left over. This puts Dan’s Cousin at about 15:36. Plus the video started at the :15 mark. So my final answer is 15:51.
Here is a link to my breakdown of groups:
http://www.evernote.com/l/AJ9vCsp_xCJNa7A0NWBoGmwWOcji58o6dAk/

By: Lia

Lia — Mon, 29 Jun 2015 17:45:37 +0000

At the end of your 3:30 video, they had almost made it to the end of the first column of names. They didn’t start calling names until several seconds into the video, but there are a couple of names left in the first column and all of the other columns are a little longer, so say each column takes about 3:30 to read. Your cousin is basically at the top of the 5th column, so there are 3 columns in between. You should set a timer for 10 minutes, 30 seconds so you can stop your timer, recover from your nap, and be ready to watch your cousin without risking missing it.

This is not super precise, but I think this is a situation where the calculation has to be quick to make it worth doing. Otherwise you can’t take a nap at all.

By: Leigh Nataro

Leigh Nataro — Mon, 29 Jun 2015 15:34:00 +0000

The first minute was about 8 people, but the pace picked up to reading 10 name per minute after that. Your cousin is the 156th name on the list. So…about 15 min 30 seconds into the reading of names you will hear your cousin’s name. Assuming you don’t start the timer until after 3 minutes have elapsed, I would set your timer for 12 min. This would give you time to rub the sleep out of your eyes, find the program thT is now on the floor and focus your phone to get a good picture for posting on Instagram.