Brain Teasers
Students earned extra recess minutes by working in teams of three to solve the following problems:
Using each operation(addition, subtraction, multiplication, division) only once, insert the correct signs to make this number sentence work.
3______5_____4_____2______6 = 12
For the following sentence you may not use addition.
1_____1______5_______2_______3 = 9
Many other problems we used are from the book Unlock the Secrets of Your Mind .
Some of these problems come from the game Master Mind.
"How Old Am I?"
In 4 years I will be three times as old as I was 4 years ago.
In 2 years I will be twice as old as I was 5 years ago.
"Chickens and Cows"
A farmer with a very clever daughter asked her to go out and count all of the chickens and cows. When she returned, she told her dad that she counted 200 legs and 50 heads. She told him that he would have to figure out how many chickens and cows from this information.
"Coins"
I have 13 coins that equal 50 cents. What combination of coins do I have?