Add 90/30 and 20/21
1st number: 3 0/30, 2nd number: 20/21
90/30 + 20/21 is 83/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
90/30 = 90 × 7/30 × 7 = 630/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
20/21 = 20 × 10/21 × 10 = 200/210 - Add the two like fractions:
630/210 + 200/210 = 630 + 200/210 = 830/210 - 830/210 simplified gives 83/21
- So, 90/30 + 20/21 = 83/21
In mixed form: 320/21
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