Add 21/80 and 27/28
21/80 + 27/28 is 687/560.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 28 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 80 × 7 = 560,
21/80 = 21 × 7/80 × 7 = 147/560 - Likewise, for the 2nd fraction, since 28 × 20 = 560,
27/28 = 27 × 20/28 × 20 = 540/560 - Add the two like fractions:
147/560 + 540/560 = 147 + 540/560 = 687/560 - So, 21/80 + 27/28 = 687/560
In mixed form: 1127/560
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