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# Adding fractions with like denominators

Sal adds 3/15+7/15. Created by Sal Khan and Monterey Institute for Technology and Education.

## Want to join the conversation?

• Does GCD mean greatest common divider. If so than how is it any different from LCM?
• Greatest common denominator
• at , Sal said that if the denominator is the same, you just add the numerator and then the denominator stays the same? I just dont get it. Is it the same on the problems without the same denominators?
• you just add the top and the bottom stays the same.
• What if your sum goes over the denominator? Say, 7/14 + 9/14. How do you deal with that?
• you still add the numerator together. Like 16/14.But this will become an improper fraction, the actual answer is 1 2/14. A mixed fraction.
• Does GCF mean greatest common factor ?
• Yes that is what it stands for
• Does the GCM equal the LCM when the BCM Is divided by the WCM?
• GCM is a greatest common multiplier and LCM is a least common multiplier. They are different.
• What would you do if a mixed number had an improper fraction in it?
• it is not completely simplified if a mixed number has an improper fraction in it
• he can just say the denominator stays the same and you add the nominator but instead hes making it confusing by reducing everything