Add 21/30 and 45/56
21/30 + 45/56 is 421/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 56 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 30 × 28 = 840,
21/30 = 21 × 28/30 × 28 = 588/840 - Likewise, for the 2nd fraction, since 56 × 15 = 840,
45/56 = 45 × 15/56 × 15 = 675/840 - Add the two like fractions:
588/840 + 675/840 = 588 + 675/840 = 1263/840 - 1263/840 simplified gives 421/280
- So, 21/30 + 45/56 = 421/280
In mixed form: 1141/280
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