Add 90/70 and 20/21
1st number: 1 20/70, 2nd number: 20/21
90/70 + 20/21 is 47/21.
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,
20/21 = 20 × 10/21 × 10 = 200/210 - Add the two like fractions:
270/210 + 200/210 = 270 + 200/210 = 470/210 - 470/210 simplified gives 47/21
- So, 90/70 + 20/21 = 47/21
In mixed form: 25/21
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