Puzzlepedia™ Brain Teasers
Math Brain Teasers
Use arithmetic to compute the answer.
Math Brain Teasers require that you do some computation to arrive at the answer. This is usually some simple arithmetic or algebra, but it can sometimes require some more advanced math, such as geometry or trigonometry.
Here is an example of a logic brain teaser that can be solved if you think carefully about adding numbers together.
An unemployed man walks into a shipping warehouse on the wharf. He goes to the foreman and asks for a job. The foreman says he`ll give him a job if he can figure out a problem with 10 bushels of apples. Nine of the bushels are full of apples weighing 1 pound each, but one bushel contains apples weighing 1.1 pounds each. All of the bushels contain the same number of apples. The foreman wants to know which bushel has the heavy apples. There is a scale, but he can only make one measurement on the scale. Making only one weight measurement, how can the man find which bushel contains the heavy apples? He can include any combination of bushels or apples on the scale.
For the answer to this logic brain teaser, check out Bushels of Apples.
Here is another math brain teaser that you can solve with some simple arithmetic.
You are on your way to visit your Grandma, who lives at the end of the valley. It's her birthday, and you want to give her the cakes you've made. Between your house and her house, you have to cross 7 bridges, and as it goes in the land of make believe, there is a troll under every bridge! Each troll, quite rightly, insists that you pay a troll toll. Before you can cross their bridge, you have to give them half of the cakes you are carrying, but as they are kind trolls, they each give you back a single cake. How many cakes do you have to leave home with to make sure that you arrive at Grandma's with exactly 2 cakes?
For the answer to this math brain teaser, check out Grandmas and Trolls. And for hundreds of more fun math brain teasers, please click the button below to view our entire collection.
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