Add 21/70 and 63/56
1st number: 21/70, 2nd number: 1 7/56
21/70 + 63/56 is 57/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 56 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 70 × 4 = 280,
21/70 = 21 × 4/70 × 4 = 84/280 - Likewise, for the 2nd fraction, since 56 × 5 = 280,
63/56 = 63 × 5/56 × 5 = 315/280 - Add the two like fractions:
84/280 + 315/280 = 84 + 315/280 = 399/280 - 399/280 simplified gives 57/40
- So, 21/70 + 63/56 = 57/40
In mixed form: 117/40
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