Add 42/49 and 21/70
42/49 + 21/70 is 81/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 70 is 490
Next, find the equivalent fraction of both fractional numbers with denominator 490 - For the 1st fraction, since 49 × 10 = 490,
42/49 = 42 × 10/49 × 10 = 420/490 - Likewise, for the 2nd fraction, since 70 × 7 = 490,
21/70 = 21 × 7/70 × 7 = 147/490 - Add the two like fractions:
420/490 + 147/490 = 420 + 147/490 = 567/490 - 567/490 simplified gives 81/70
- So, 42/49 + 21/70 = 81/70
In mixed form: 111/70
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