Add 21/30 and 5/7
21/30 + 5/7 is 99/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 7 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Likewise, for the 2nd fraction, since 7 × 30 = 210,
5/7 = 5 × 30/7 × 30 = 150/210 - Add the two like fractions:
147/210 + 150/210 = 147 + 150/210 = 297/210 - 297/210 simplified gives 99/70
- So, 21/30 + 5/7 = 99/70
In mixed form: 129/70
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