Add 21/84 and 54/70
21/84 + 54/70 is 143/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
54/70 = 54 × 6/70 × 6 = 324/420 - Add the two like fractions:
105/420 + 324/420 = 105 + 324/420 = 429/420 - 429/420 simplified gives 143/140
- So, 21/84 + 54/70 = 143/140
In mixed form: 13/140
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