Add 21/70 and 28/21
1st number: 21/70, 2nd number: 1 7/21
21/70 + 28/21 is 49/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
28/21 = 28 × 10/21 × 10 = 280/210 - Add the two like fractions:
63/210 + 280/210 = 63 + 280/210 = 343/210 - 343/210 simplified gives 49/30
- So, 21/70 + 28/21 = 49/30
In mixed form: 119/30
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