Add 20/42 and 21/49
20/42 + 21/49 is 19/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 49 is 294
Next, find the equivalent fraction of both fractional numbers with denominator 294 - For the 1st fraction, since 42 × 7 = 294,
20/42 = 20 × 7/42 × 7 = 140/294 - Likewise, for the 2nd fraction, since 49 × 6 = 294,
21/49 = 21 × 6/49 × 6 = 126/294 - Add the two like fractions:
140/294 + 126/294 = 140 + 126/294 = 266/294 - 266/294 simplified gives 19/21
- So, 20/42 + 21/49 = 19/21
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