Add 21/60 and 18/28
21/60 + 18/28 is 139/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 28 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 28 × 15 = 420,
18/28 = 18 × 15/28 × 15 = 270/420 - Add the two like fractions:
147/420 + 270/420 = 147 + 270/420 = 417/420 - 417/420 simplified gives 139/140
- So, 21/60 + 18/28 = 139/140
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