Deep Thought

A platform for seeking the answers to the meaning of Life, the Universe, and Everything.

Welcome to Deep Thought! At ideas42, our work involves tackling some of our world’s toughest problems. Naturally, when we need a little downtime, we unwind by solving some of the internet’s toughest puzzles.

In the spirit of a few of our core values—generosity, playfulness, and perhaps even tenacity—we’re excited to share puzzles so that you too can get one step closer to correctly answering the ultimate questions (hint: it won’t always be 42), while also (hopefully) having a bit of fun.


In 1973, UC Berkeley was wary of being sued for gender discrimination. The evidence against them seemed pretty bad – only 35% of female students who applied were admitted, while 44% of male applicants were admitted.

To get a better understanding of which departments were contributing to this gender discrimination, they took a deeper dive into the data behind each department’s admission rates. Once they looked at each subset contributing to the aggregate data that got them into trouble in the first place, they saw a different story. Out of the six departments, four accepted more women than men. In actuality, the gender bias was in the women’s favor.

So, why did the aggregated data and the categorical data tell a completely different story? There is a confounding variable that is hidden from sight when you look at the data – can you spot it?


Think you have the answer? Submit your answer here.


To submit your own Deep Thought weekly puzzle, contact us at


Solution to previous puzzle

Previous puzzle:

You had 10 lbs of cucumbers, each of which consisted of 99% water. After leaving them in the sun, some of the water in the cucumbers evaporated. If the cucumbers ended up with 98% water in them, how much of their weight did they lose?


The cucumbers lost half their weight. If the water was 99% of the total weight, the remaining substance must have weighed 0.1lbs. If after the evaporation the substance comprises 2% = 1/50 of the cucumbers, the total weight must be 50 x 0.1lbs = 5lbs.

Congratulations to the winners:

Gwyneth; Singapore, Singapore
Julia Oran; Chicago, IL
Thomas; Amsterdam, Netherlands
Ted; Austin, Texas
Jim; Austin, Texas
Juandi Castrillon; Weston, FL
Anna Thompson; San Francisco, CA

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