Add 21/28 and 9/80
21/28 + 9/80 is 69/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 80 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 28 × 20 = 560,
21/28 = 21 × 20/28 × 20 = 420/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
9/80 = 9 × 7/80 × 7 = 63/560 - Add the two like fractions:
420/560 + 63/560 = 420 + 63/560 = 483/560 - 483/560 simplified gives 69/80
- So, 21/28 + 9/80 = 69/80
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