Add 18/60 and 72/21
1st number: 18/60, 2nd number: 3 9/21
18/60 + 72/21 is 261/70.
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,
72/21 = 72 × 20/21 × 20 = 1440/420 - Add the two like fractions:
126/420 + 1440/420 = 126 + 1440/420 = 1566/420 - 1566/420 simplified gives 261/70
- So, 18/60 + 72/21 = 261/70
In mixed form: 351/70
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