Add 20/70 and 21/49
20/70 + 21/49 is 5/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 49 is 490
Next, find the equivalent fraction of both fractional numbers with denominator 490 - For the 1st fraction, since 70 × 7 = 490,
20/70 = 20 × 7/70 × 7 = 140/490 - Likewise, for the 2nd fraction, since 49 × 10 = 490,
21/49 = 21 × 10/49 × 10 = 210/490 - Add the two like fractions:
140/490 + 210/490 = 140 + 210/490 = 350/490 - 350/490 simplified gives 5/7
- So, 20/70 + 21/49 = 5/7
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