Add 21/36 and 20/42
21/36 + 20/42 is 89/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 42 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
21/36 = 21 × 7/36 × 7 = 147/252 - Likewise, for the 2nd fraction, since 42 × 6 = 252,
20/42 = 20 × 6/42 × 6 = 120/252 - Add the two like fractions:
147/252 + 120/252 = 147 + 120/252 = 267/252 - 267/252 simplified gives 89/84
- So, 21/36 + 20/42 = 89/84
In mixed form: 15/84
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