Add 42/84 and 21/70
42/84 + 21/70 is 4/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 70 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 70 × 6 = 420,
21/70 = 21 × 6/70 × 6 = 126/420 - Add the two like fractions:
210/420 + 126/420 = 210 + 126/420 = 336/420 - 336/420 simplified gives 4/5
- So, 42/84 + 21/70 = 4/5
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