Add 30/70 and 80/84
30/70 + 80/84 is 29/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 70 × 6 = 420,
30/70 = 30 × 6/70 × 6 = 180/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
80/84 = 80 × 5/84 × 5 = 400/420 - Add the two like fractions:
180/420 + 400/420 = 180 + 400/420 = 580/420 - 580/420 simplified gives 29/21
- So, 30/70 + 80/84 = 29/21
In mixed form: 18/21
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