/ means separate from fraction numerator and denominator can you tell the least common denaminator and than tell how you solved it
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1/8 + 8/9
9/72 + 64/72
73/72
1 1/72
Least common denominators can be a little tricky. basically you have to find the smallest number that all denominator are divisible by. In this case the only common denominator is 72. and this is simply 9*8.
Whenever I do fractions if I dont have to find the least common denomintaor I just multiply the two denominators togethers. This will give me a common denominator to work from and will produce a correct answer. It's just sometimes I have to work with slightly larger numbers. howveer do not do this if the instructions state you need a Lowest common denominator.
Once you have the LCD you just multiply the numerator by the factor needed to get the denomintaor.
so 1/8 I have to mulitply 8 by 9 to get 72. So I have to mulitply 1 by 9. 1/8 = 9/72
8/9 (mulitply both numerator and denominator by 8 8/9 = 64/72
Then just add the numerator together, 9+64 = 73
Denomintor stays the same at 72
73/72 73 is greater so we get a whole 1 and 1 /72 left over.
9/72 + 64/72
73/72
1 1/72
Least common denominators can be a little tricky. basically you have to find the smallest number that all denominator are divisible by. In this case the only common denominator is 72. and this is simply 9*8.
Whenever I do fractions if I dont have to find the least common denomintaor I just multiply the two denominators togethers. This will give me a common denominator to work from and will produce a correct answer. It's just sometimes I have to work with slightly larger numbers. howveer do not do this if the instructions state you need a Lowest common denominator.
Once you have the LCD you just multiply the numerator by the factor needed to get the denomintaor.
so 1/8 I have to mulitply 8 by 9 to get 72. So I have to mulitply 1 by 9. 1/8 = 9/72
8/9 (mulitply both numerator and denominator by 8 8/9 = 64/72
Then just add the numerator together, 9+64 = 73
Denomintor stays the same at 72
73/72 73 is greater so we get a whole 1 and 1 /72 left over.
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New term: Least Common Multiple
(common = shared, least = smallest) so we could say, "the smallest number that is a multiple of both."
Example: given 12 and 18, what is the SMALLEST number DIVISIBLE by both 12 and 18?
answer: 36
This means: 36 is the Least Common Multiple
(common = shared, least = smallest)
When you ADD fractions, you have to set the DENOMINATOR (bottom term) of both fractions to the same, by multiplying by n/n, where you select the correct n.
Fist step: What is the Least Common Multiple of the denominators (8 and 9)? In this case, 72 or 8x9 is the LCM.
1/8 x 9/9 = 9/72
8/9 x 8/8 = 64/72
NOW you can add: (9 + 64) / 72 = 73/72
(common = shared, least = smallest) so we could say, "the smallest number that is a multiple of both."
Example: given 12 and 18, what is the SMALLEST number DIVISIBLE by both 12 and 18?
answer: 36
This means: 36 is the Least Common Multiple
(common = shared, least = smallest)
When you ADD fractions, you have to set the DENOMINATOR (bottom term) of both fractions to the same, by multiplying by n/n, where you select the correct n.
Fist step: What is the Least Common Multiple of the denominators (8 and 9)? In this case, 72 or 8x9 is the LCM.
1/8 x 9/9 = 9/72
8/9 x 8/8 = 64/72
NOW you can add: (9 + 64) / 72 = 73/72