Add 18/60 and 81/21
1st number: 18/60, 2nd number: 3 18/21
18/60 + 81/21 is 291/70.
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,
81/21 = 81 × 20/21 × 20 = 1620/420 - Add the two like fractions:
126/420 + 1620/420 = 126 + 1620/420 = 1746/420 - 1746/420 simplified gives 291/70
- So, 18/60 + 81/21 = 291/70
In mixed form: 411/70
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