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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?

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.

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.