Add 30/21 and 12/45
1st number: 1 9/21, 2nd number: 12/45
30/21 + 12/45 is 178/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
30/21 = 30 × 15/21 × 15 = 450/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
12/45 = 12 × 7/45 × 7 = 84/315 - Add the two like fractions:
450/315 + 84/315 = 450 + 84/315 = 534/315 - 534/315 simplified gives 178/105
- So, 30/21 + 12/45 = 178/105
In mixed form: 173/105
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