Add 21/35 and 9/42
21/35 + 9/42 is 57/70.
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,
9/42 = 9 × 5/42 × 5 = 45/210 - Add the two like fractions:
126/210 + 45/210 = 126 + 45/210 = 171/210 - 171/210 simplified gives 57/70
- So, 21/35 + 9/42 = 57/70
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