A girl is twice as old as her brother and half as old as her father. In 50 years, her brother will be half as old as his father. How old is the daughter now?
A brand new Mobile Phone was on sale at 20% as a promotional offer. By what per cent must the Mobile price be increased to sell it at the original price again?
In a school, there are four subjects. Seventy percent of students study English, seventy five percent of students study Science, eighty five percent of students study Mathematics and eighty percent of students study Spanish.
Can you calculate the percentage of students that study all four subjects?
Samuel was out for a walk when it started to rain. He did not have an umbrella and he wasn't wearing a hat. His clothes were soaked, yet not a single hair on his head got wet. How could this happen?
The day before the 1996 U.S. presidential election, the NYT Crossword contained the clue “Lead story in tomorrow’s newspaper,” the puzzle was built so that both electoral outcomes were correct answers, requiring 7 other clues to have dual responses.