Add 9/21 and 90/70
1st number: 9/21, 2nd number: 1 20/70
9/21 + 90/70 is 12/7.
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,
9/21 = 9 × 10/21 × 10 = 90/210 - Likewise, for the 2nd fraction, since 70 × 3 = 210,
90/70 = 90 × 3/70 × 3 = 270/210 - Add the two like fractions:
90/210 + 270/210 = 90 + 270/210 = 360/210 - 360/210 simplified gives 12/7
- So, 9/21 + 90/70 = 12/7
In mixed form: 15/7
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