Add 90/70 and 30/21
1st number: 1 20/70, 2nd number: 1 9/21
90/70 + 30/21 is 19/7.
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,
90/70 = 90 × 3/70 × 3 = 270/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
30/21 = 30 × 10/21 × 10 = 300/210 - Add the two like fractions:
270/210 + 300/210 = 270 + 300/210 = 570/210 - 570/210 simplified gives 19/7
- So, 90/70 + 30/21 = 19/7
In mixed form: 25/7
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