Add 21/35 and 28/42
21/35 + 28/42 is 19/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 35 × 6 = 210,
21/35 = 21 × 6/35 × 6 = 126/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
28/42 = 28 × 5/42 × 5 = 140/210 - Add the two like fractions:
126/210 + 140/210 = 126 + 140/210 = 266/210 - 266/210 simplified gives 19/15
- So, 21/35 + 28/42 = 19/15
In mixed form: 14/15
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