Add 21/28 and 75/80
21/28 + 75/80 is 27/16.
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,
75/80 = 75 × 7/80 × 7 = 525/560 - Add the two like fractions:
420/560 + 525/560 = 420 + 525/560 = 945/560 - 945/560 simplified gives 27/16
- So, 21/28 + 75/80 = 27/16
In mixed form: 111/16
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