Replace the question mark with a number
MATH PUZZLE: Can you replace the question mark with a number?Correct answers: 566
The first user who solved this task is Sanja Šabović.
#brainteasers #math #riddles
First U.S. railroad using the telephoneIn 1877, a trial test of a telephone was given in the Pennsylvania Railroad Company shops by associates of Alexander Graham Bell. The company was impressed by the demonstration and became the first to make a permanent installation.«* |