Add 18/21 and 28/60
18/21 + 28/60 is 139/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 60 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
18/21 = 18 × 20/21 × 20 = 360/420 - Likewise, for the 2nd fraction, since 60 × 7 = 420,
28/60 = 28 × 7/60 × 7 = 196/420 - Add the two like fractions:
360/420 + 196/420 = 360 + 196/420 = 556/420 - 556/420 simplified gives 139/105
- So, 18/21 + 28/60 = 139/105
In mixed form: 134/105
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