Add 21/42 and 18/35
21/42 + 18/35 is 71/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 35 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Likewise, for the 2nd fraction, since 35 × 6 = 210,
18/35 = 18 × 6/35 × 6 = 108/210 - Add the two like fractions:
105/210 + 108/210 = 105 + 108/210 = 213/210 - 213/210 simplified gives 71/70
- So, 21/42 + 18/35 = 71/70
In mixed form: 11/70
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