Adding and subtracting fractions

5 videos
3 skills
You've already got 2 cups of sugar in the cupboard. Your grandmother's recipe for disgustingly-sweet-fudge-cake calls for 3 and 1/3 cups of sugar. How much sugar do you need to borrow from you robot neighbor? Adding and subtracting fractions is key. It might be a good idea to look at the equivalent fractions tutorial before tackling this one.

Adding fractions with like denominators

VIDEO 3:18 minutes
With like denominators, you're basically just adding numerators. That's not too bad, right? Can the resulting fraction be simplified?

Adding fractions with common denominators

PRACTICE PROBLEMS
Add two fractions with the like denominators.  

Subtracting fractions with like denominators

VIDEO 2:26 minutes
Just like when we added...subtracting fractions is pretty straightforward when the two fractions have like denominators.

Subtracting fractions with common denominators

PRACTICE PROBLEMS
Solve a subtraction problem with two fractions with like denominators.  

Word problem: What fraction of spider eyes are looking at me?

VIDEO 1:45 minutes
You mean a spider has MORE than 2 eyes? Yikes!

Word problem: What fraction of an hour should the piano still be practiced?

VIDEO 3:04 minutes
Better get practicing, Pedro! You have exactly (a fraction) more of an hour to practice the piano.

Word problem: How long is this lizard?

VIDEO 2:29 minutes
Add the fractions to find out how long this lizard is.

Adding and subtracting fractions with like denominators word problems

PRACTICE PROBLEMS
Practice solving word problems by adding and sutbracting fractions. The fractions used in these problems have like (or common) denominators.