Add 18/36 and 72/21
1st number: 18/36, 2nd number: 3 9/21
18/36 + 72/21 is 55/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 21 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
18/36 = 18 × 7/36 × 7 = 126/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
72/21 = 72 × 12/21 × 12 = 864/252 - Add the two like fractions:
126/252 + 864/252 = 126 + 864/252 = 990/252 - 990/252 simplified gives 55/14
- So, 18/36 + 72/21 = 55/14
In mixed form: 313/14
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