Add 21/60 and 30/21
1st number: 21/60, 2nd number: 1 9/21
21/60 + 30/21 is 249/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 60 × 7 = 420,
21/60 = 21 × 7/60 × 7 = 147/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
30/21 = 30 × 20/21 × 20 = 600/420 - Add the two like fractions:
147/420 + 600/420 = 147 + 600/420 = 747/420 - 747/420 simplified gives 249/140
- So, 21/60 + 30/21 = 249/140
In mixed form: 1109/140
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