Add 3/45 and 28/21
1st number: 3/45, 2nd number: 1 7/21
3/45 + 28/21 is 7/5.
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,
3/45 = 3 × 7/45 × 7 = 21/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
28/21 = 28 × 15/21 × 15 = 420/315 - Add the two like fractions:
21/315 + 420/315 = 21 + 420/315 = 441/315 - 441/315 simplified gives 7/5
- So, 3/45 + 28/21 = 7/5
In mixed form: 12/5
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