Add 21/28 and 42/49
21/28 + 42/49 is 45/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 49 is 196
Next, find the equivalent fraction of both fractional numbers with denominator 196 - For the 1st fraction, since 28 × 7 = 196,
21/28 = 21 × 7/28 × 7 = 147/196 - Likewise, for the 2nd fraction, since 49 × 4 = 196,
42/49 = 42 × 4/49 × 4 = 168/196 - Add the two like fractions:
147/196 + 168/196 = 147 + 168/196 = 315/196 - 315/196 simplified gives 45/28
- So, 21/28 + 42/49 = 45/28
In mixed form: 117/28
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