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### Course: Arithmetic (all content)>Unit 5

Lesson 15: Adding and subtracting fractions with unlike denominators

# Adding and subtracting 3 fractions

Learn how to add and subtract fractions with unlike denominators. They watch the process of finding a common denominator, then practice adding and subtracting the fractions to solve the problems.

## Want to join the conversation?

• What do I do if I have three minuses?
• Same thing as normal, unless if the answer goes into negatives which isn't likely.
• Why are the questions hard
• Cause they want you to struggle
• hi I need help do you how to do this
• Find the LCM then change that to the LCD and then subtract, add, multiply, divide. ( LCM means least common multiple) (LCD means least common denominator)
• if order of opperations is exponenents, x divition, addition, subtraction. wouldn't the secound awsner be -1/18
• what is

\[\dfrac{3}{5} + \dfrac{7}{10} - \dfrac{1}{2} = \]
• 3/5 + 7/10 - 1/2 = 4/5
(1 vote)
• Thank you now i know how to add or subtract three fractions. again thank you
• Why didn't this follow BEDMAS? 8-3+6, shouldn't that equal -1?
• 8-3 = 5
and then 5+6 = 11
• It doesn't make sense when the top number is more than the demoninator on the worksheet