Add 90/30 and 30/21
1st number: 3 0/30, 2nd number: 1 9/21
90/30 + 30/21 is 31/7.
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,
30/21 = 30 × 10/21 × 10 = 300/210 - Add the two like fractions:
630/210 + 300/210 = 630 + 300/210 = 930/210 - 930/210 simplified gives 31/7
- So, 90/30 + 30/21 = 31/7
In mixed form: 43/7
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