Add 30/70 and 18/21
30/70 + 18/21 is 9/7.
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,
30/70 = 30 × 3/70 × 3 = 90/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
18/21 = 18 × 10/21 × 10 = 180/210 - Add the two like fractions:
90/210 + 180/210 = 90 + 180/210 = 270/210 - 270/210 simplified gives 9/7
- So, 30/70 + 18/21 = 9/7
In mixed form: 12/7
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