Add 21/45 and 28/21
1st number: 21/45, 2nd number: 1 7/21
21/45 + 28/21 is 9/5.
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,
21/45 = 21 × 7/45 × 7 = 147/315 - Likewise, for the 2nd fraction, since 21 × 15 = 315,
28/21 = 28 × 15/21 × 15 = 420/315 - Add the two like fractions:
147/315 + 420/315 = 147 + 420/315 = 567/315 - 567/315 simplified gives 9/5
- So, 21/45 + 28/21 = 9/5
In mixed form: 14/5
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