31 Brain Puzzles
Logic and number teasers, answers included. Give each puzzle sixty seconds before you read the answer. Most of them have a trap; spotting it is the fun.
On iPhone or iPad
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Read the first few
Day 1
A bat and a ball cost $1.10 together. The bat costs $1.00 more than the ball. How much is the ball?
Give it 60 seconds before you look.
Answer: 5 cents. (Bat $1.05 + ball $0.05 = $1.10.)
Day 2
What comes next: 2, 6, 12, 20, 30, ?
Give it 60 seconds before you look.
Answer: 42. The gaps go 4, 6, 8, 10, 12.
Day 3
If 5 machines make 5 widgets in 5 minutes, how long do 100 machines take to make 100 widgets?
Give it 60 seconds before you look.
Answer: 5 minutes. Each machine makes one widget in 5 minutes.
Where this comes from
The book is drawn from Cognilo, a free iPhone app. If you like the format, the app has more.
Free to read, print and share unchanged. Please don't sell it. Also available as a free calendar subscription.