Add 21/40 and 63/84
21/40 + 63/84 is 51/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 84 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
21/40 = 21 × 21/40 × 21 = 441/840 - Likewise, for the 2nd fraction, since 84 × 10 = 840,
63/84 = 63 × 10/84 × 10 = 630/840 - Add the two like fractions:
441/840 + 630/840 = 441 + 630/840 = 1071/840 - 1071/840 simplified gives 51/40
- So, 21/40 + 63/84 = 51/40
In mixed form: 111/40
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