Add 90/30 and 90/21
1st number: 3 0/30, 2nd number: 4 6/21
90/30 + 90/21 is 51/7.
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,
90/21 = 90 × 10/21 × 10 = 900/210 - Add the two like fractions:
630/210 + 900/210 = 630 + 900/210 = 1530/210 - 1530/210 simplified gives 51/7
- So, 90/30 + 90/21 = 51/7
In mixed form: 72/7
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