Add 15/42 and 21/35
15/42 + 21/35 is 67/70.
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,
15/42 = 15 × 5/42 × 5 = 75/210 - Likewise, for the 2nd fraction, since 35 × 6 = 210,
21/35 = 21 × 6/35 × 6 = 126/210 - Add the two like fractions:
75/210 + 126/210 = 75 + 126/210 = 201/210 - 201/210 simplified gives 67/70
- So, 15/42 + 21/35 = 67/70
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