Michael Cieply for The New York Times:

The Interviewgenerated roughly $15 million in online sales and rentals during its first four days of availability, Sony Pictures said on Sunday. Sony did not say how much of that total represented $6 digital rentals versus $15 sales. The studio said there were about two million transactions over all.

**Featured Comment**

Stas, with a zinger for the ages:

Probably they took advice from this guy.

Angela Ensminger:

Maybe an opening question to this problem would be:. Do you think Sony had more rentals or more sales? This could lead to some interesting discussions before actually solving the problem.

[h/t Math Curmudgeon]

## 20 Comments

## Kyle Pearce

December 29, 2014 - 12:09 pm -You might get another side job with NY Times, if you keep that up!

Would be great to get students to send in their solutions. Just bombard them with it. Could prompt an article with a title like: “Math: More useful in the real world than society realizes!”

I’m sure we could do better on the title.

## Alex Kluge (@AlexVKluge)

December 29, 2014 - 12:11 pm -Excellant! So many time we can pull teaching examples from interesting headlines for, hopefully, much more engaging instruction and great examples of critical thinking and analysis.

## Dennis Ashendorf

December 29, 2014 - 12:48 pm -I don’t think that the $15 sales make sense. My tickets were $10. Who pays $15 – NYC residents? What was the average ticket price? Another question to ask students.

## @aanthonya

December 29, 2014 - 2:14 pm -This is why I love your blog. I read the same story and didn’t even think about the math or to set up a system. This is truly the kind of stuff that will connect with many students. Real story, interesting, current, real math, real money. Thank you.

@aanthonya

## Dan Dawson

December 29, 2014 - 3:10 pm -Dennis: I believe the $15 sales were the sales of the online digital version, not theater ticket prices. The quote from the story above doesn’t actually bring ticket sales in to the equation at all.

For example, Google Play, X-Box Video and YouTube had it for rent at $5.99 and for sale at $14.99, and Sony’s seetheinterview.com had it for rent for $5.99, so pricing was the same across all platforms, so at least that kept the math easy!

## Stas

December 29, 2014 - 6:42 pm -Probably they took advice from this guy

http://www.nytimes.com/2012/07/29/opinion/sunday/is-algebra-necessary.html

## Dan Meyer

December 29, 2014 - 8:29 pm -Feature that comment and break out the burn cream!

## Glenn Blakney

December 30, 2014 - 6:36 am -Or, conversely, maybe we should compensate Mr. Cieply for providing us with such an elegant word problem? Think of the money we could save: instead of textbooks, we could just subscribe to the Times!

## Angela Ensminger

December 30, 2014 - 8:58 am -I am so glad I am not the only one who thought this. I had quickly calculated a reasonable estimate as I read the article. Maybe an opening question to this problem would be:. Do you think Sony had more rentals or more sales? This could lead to some interesting discussions before actually solving the problem.

## Dan Meyer

December 30, 2014 - 9:00 am -@

Angela, love it. Added your suggestion to the main post.## Dan Meyer

December 30, 2014 - 8:33 pm -@

Stas, I tweeted your connection to the Algebra op-ed. Went pretty far.## Stas

December 30, 2014 - 8:59 pm -@Dan, they’ve also recently shut down their chess column that was run for 50 years. So, their shift in values is clear. But considering that newspapers are almost dead nowadays, not a big deal. There are enough intelligent blog writers and twitter users to read :-).

## James Cleveland

December 30, 2014 - 9:50 pm -Since many people tweeted about how those numbers are rough and canâ€™t make an exact answer, maybe a graph more like this one is more illuminating:

https://www.desmos.com/calculator/niy8kpeuow

## Stas

December 30, 2014 - 9:57 pm -For more, advanced/curious readers, this is the reference:

https://en.wikipedia.org/wiki/Numerical_stability#Stability_in_numerical_linear_algebra

## Stas

December 30, 2014 - 10:33 pm -Concretely, each dollar away from “roughly $15 million” changes x and y by 1/9 (in the opposite directions); each transaction away from “about two million” changes x by 5/3 and y by 2/3 (also in the opposite directions). Here is how to find it with Wolfram Alpha.

## @jouborg

January 1, 2015 - 12:47 pm -Detailed steps using pen and paper using simultaneous equations: https://twitter.com/jouborg/status/549963741249286145

## Stacie

January 4, 2015 - 5:48 pm -Dan, I love your thoughts on making math more relevant to students in your TED talk. My past students have never taken ownership in the cost of online piracy. I took your post a step further in http://systry.com/how-much-does-piracy-cost/.

## Joshua

January 5, 2015 - 7:47 am -To the earlier ideas about making this a focus of a math exploration, I’m on the fence about whether this is an interesting question. I mean, frankly, I don’t really care how many rentals vs sales they had and I’m the kind of person who solves systems of equations for fun, so will kids?

On the other hand, a discussion about whether it is better to rent or buy movies? That sounds interesting and could probably incorporate many of the same concepts from algebra.

## Laura

January 6, 2015 - 12:47 pm -Hi Dan, I loved this article and all the comments below it. One comment mentioned your TEDxNYED talk, so I just watched that too. Loved it! I used to teach high school math (mostly Geometry and Algebra 2) and you are so on-target about how to adjust the problem to encourage patient problem solving, deeper understanding, and better student engagement! Keep up the great work! :)

Your TED talk video link if others want to find it quickly: http://www.ted.com/talks/dan_meyer_math_curriculum_makeover?language=en#t-681342

## Bowen Kerins

January 6, 2015 - 6:21 pm -OMG NEW DATA

http://www.usatoday.com/story/life/movies/2015/01/06/the-interview-online-sales-totals/21354589/

$31 million on 4.3 million sales, $5.99 to rent, $14.99 to buy.