Add 12/21 and 90/70
1st number: 12/21, 2nd number: 1 20/70
12/21 + 90/70 is 13/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 70 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
12/21 = 12 × 10/21 × 10 = 120/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
90/70 = 90 × 3/70 × 3 = 270/210 - Add the two like fractions:
120/210 + 270/210 = 120 + 270/210 = 390/210 - 390/210 simplified gives 13/7
- So, 12/21 + 90/70 = 13/7
In mixed form: 16/7
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