Add 18/60 and 18/21
18/60 + 18/21 is 81/70.
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,
18/60 = 18 × 7/60 × 7 = 126/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
18/21 = 18 × 20/21 × 20 = 360/420 - Add the two like fractions:
126/420 + 360/420 = 126 + 360/420 = 486/420 - 486/420 simplified gives 81/70
- So, 18/60 + 18/21 = 81/70
In mixed form: 111/70
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