Add 42/84 and 21/35
42/84 + 21/35 is 11/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 35 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
42/84 = 42 × 5/84 × 5 = 210/420 - Likewise, for the 2nd fraction, since 35 × 12 = 420,
21/35 = 21 × 12/35 × 12 = 252/420 - Add the two like fractions:
210/420 + 252/420 = 210 + 252/420 = 462/420 - 462/420 simplified gives 11/10
- So, 42/84 + 21/35 = 11/10
In mixed form: 11/10
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