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• How do I add fractions to fractions? Fractions lesson 6 Integrated 1A
• What is ?
• One way to do this is to draw pictures and cut them up and combine them.
• There is a better way
• This is the part that confuses students most often.
• You must sometimes change fractions to show the same type of parts.
• Using equal fractions makes this easier.
View slide
• Let’s begin with equal fractions.
• Let’s start with one half and make a list of equal fractions.
Make a new fraction that is equal to one half. Multiply the top number (1) by 2. Multiply the bottom number by the same 2. View slide
• Let’s multiply one half by
• Now our list should look like this.
• Let’s add another fraction to our list in our notebook.
• Start with the first number – one half. Multiply top and bottom by 4 this time.
• Write the new fraction.
• What comes next? Write the new fraction.
• Continue this list in your notebook.
• What comes next? Write the new fractions.
• Let’s multiply one third by
• Now our list should look like this.
• A new list
• Multiply the top and bottom by three. Do the same for the next one by multiplying one-third by four.
• Going from the known to the unknown
• In a previous lesson last week, you divided top and bottom by the same number.
• You didn’t change the value of the fraction, just the appearance.
• Is one-fourth equal to two-eighths?
• Add these two fractions making them both a certain number of eighths We can’t easily add fourths to eighths so we find a number to multiply times four to get eight on the bottom. x2 x2
• We are making a addition problem that becomes easier to work with. One eighth doesn’t need to be changed, So just rewrite it. x2 x2
• Now add down the right side. Six-eighths plus one-eighth is how many eighths? 7
• Get a worksheet (F6)
• What is the least common multiple of four and 8?
• (What is the smallest number in both lists?)
• Use eight as your common denominator.
Multiples of 4: 4, 8, 12, 16, 20, 24… Multiples of 8: 8, 16, 24, 32… Terms :
• Make your denominators the same.
• What can you multiply by four to get eight?
• The bottom number is already in eighths, don’t change it
x2 x2
• Now add the column with the common denominators
• Is five-eighths in simplest form?
x2 x2
• Worksheet #5
• What is the least common multiple of 2 and 6?
• (What is the smallest number in both lists?)
• Use SIX as your common denominator.
Multiples of 2: 2, 4, 6, 8, 10, 12, 14, 16… Multiples of 6: 6, 12, 18, 24, 30…
• Make your denominators the same.
• What can you multiply by two to get six?
• The bottom number is already in sixths, don’t change it
x? x?
• Add down the right column.