Correlation coefficients range from -1 to +1, indicating the strength of relationships between variables. Investors use correlation coefficients for portfolio diversification to reduce risk.

Calculating stock growth rates can be challenging and seem intimidating, especially with all the numbers and terminology getting thrown around. Every investor has a preferred way of calculating that ...

Students in Melissa Williams' kindergarten class at the Westminster School in Atlanta, Georgia, practice connecting quantities to written numbers — a key part of number sense. Credit: Holly Korbey for ...

Students in Kristen Gonsoir’s classroom at Groton Area High School in Groton, S.D., spend a lot of time solving equations together. Early this school year, they passed almost an entire period working ...