Add 21/30 and 40/56
21/30 + 40/56 is 99/70.
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,
40/56 = 40 × 15/56 × 15 = 600/840 - Add the two like fractions:
588/840 + 600/840 = 588 + 600/840 = 1188/840 - 1188/840 simplified gives 99/70
- So, 21/30 + 40/56 = 99/70
In mixed form: 129/70
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