Add 30/45 and 90/21
1st number: 30/45, 2nd number: 4 6/21
30/45 + 90/21 is 104/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 21 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
30/45 = 30 × 7/45 × 7 = 210/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
90/21 = 90 × 15/21 × 15 = 1350/315 - Add the two like fractions:
210/315 + 1350/315 = 210 + 1350/315 = 1560/315 - 1560/315 simplified gives 104/21
- So, 30/45 + 90/21 = 104/21
In mixed form: 420/21
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