Add 3/7 and 21/36
3/7 + 21/36 is 85/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 7 × 36 = 252,
3/7 = 3 × 36/7 × 36 = 108/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
21/36 = 21 × 7/36 × 7 = 147/252 - Add the two like fractions:
108/252 + 147/252 = 108 + 147/252 = 255/252 - 255/252 simplified gives 85/84
- So, 3/7 + 21/36 = 85/84
In mixed form: 11/84
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