MAGIC SQUARE: Calculate A-B+C
The aim is to place the some numbers from the list (3, 4, 6, 7, 8, 9, 10, 16, 18, 19, 21, 84, 99) into the empty squares and squares marked with A, B an C. Sum of each row and column should be equal. All the numbers of the magic square must be different. Find values for A, B, and C. Solution is A-B+C.Correct answers: 45
The first user who solved this task is Sanja Šabović.
#brainteasers #math #magicsquare
Ballpen in space
When NASA first started sending up astronauts, they quickly discovered that ballpoint pens would not work in zero gravity.
To combat the problem, NASA scientists spent a decade and $12 billion to develop a pen that writes in zero gravity, upside down, underwater, on almost any surface including glass and at temperatures ranging from below freezing to 300 C.
The Russians used a pencil.