Add 20/21 and 7/30
20/21 + 7/30 is 83/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
20/21 = 20 × 10/21 × 10 = 200/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
7/30 = 7 × 7/30 × 7 = 49/210 - Add the two like fractions:
200/210 + 49/210 = 200 + 49/210 = 249/210 - 249/210 simplified gives 83/70
- So, 20/21 + 7/30 = 83/70
In mixed form: 113/70
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