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