Youtube videos by Julie Harland are organized at http://YourMathGal.com. Shows how to use algebra to solve this age problem: The sum of the ages of two cousins, Carlos and Maria, is 31 years. Three years ago, Carlos was four times the age of Maria. How old are they now?
age3.mp4<br />For more great math videos visit: www.youtube.com/user/videosbyjulieharland/videos