How many coins can touch one coin, or how many basketballs can "kiss" one basketball at the same time? This seemingly playful ...

National security, unlocked. Each Thursday, host Mary Louise Kelly and a team of NPR correspondents discuss the biggest national security news of the week. With decades of reporting from battlefields ...

Julia Kagan is a financial/consumer journalist and former senior editor, personal finance, of Investopedia. Westend61 / Getty Images The annualized income installment method calculates estimated tax ...

Statistical methods are mathematical formulas, models, and techniques that are used in statistical analysis of raw research data. The application of statistical methods extracts information from ...

Daniel Liberto is a journalist with over 10 years of experience working with publications such as the Financial Times, The Independent, and Investors Chronicle. Investopedia / Eliana Rodgers ...