Tricky 'If it takes 5 machines 5 minutes' puzzle will have you scratching your head

A puzzle that begins with ‘If it takes 5 machines 5 minutes to make 5 widgets’ has taken over social media this month and left everyone confused. Find the full conundrum below and the answer if you’re scratching your head.

It’s from something called the Cognitive Reflection Test (CRT) which is the world’s shortest IQ test at just three questions long. The CRT was originally part of a research paper published in 2005 by psychologist Shane Frederick. Now, it’s gone viral online…

‘If it takes 5 machines 5 minutes’ puzzle

The puzzle has been circling social media for years but has seen a resurgence in 2023. It goes like this…

• If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets?

So, what’s the answer? Find out below.

Answer to the confusing IQ puzzle

If you’re struggling, you’re not the only one. In fact, a whopping 83 percent of people the professor gave the test to failed and got at least one of the questions wrong.

Lots of people assume it’s 100, but the real answer is…

Each machine takes 5 minutes to make 1 widget. So, it will still only take 5 minutes for 100 machines to make 100 widgets.

It’s easy when you think about it! Now have a go at the ‘If you multiply this number by any other number’ riddle which is also stumping everyone.

The other two CRT questions

If you want to test your brain some more, here are the other two questions from the tricky CRT test…

1. A bat and a ball cost $1.10 in total. The bat costs $1 more than the ball. How much does the ball cost?
2. In a lake, there is a patch of lily pads. Every day, the patch doubles in size. If it takes 48 days for the patch to cover the entire lake, how long would it take for the patch to cover half of the lake?

Here are the answers…

1. 5 cents
2. 47 days

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