Add 72/84 and 30/70
72/84 + 30/70 is 9/7.
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,
72/84 = 72 × 5/84 × 5 = 360/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
30/70 = 30 × 6/70 × 6 = 180/420 - Add the two like fractions:
360/420 + 180/420 = 360 + 180/420 = 540/420 - 540/420 simplified gives 9/7
- So, 72/84 + 30/70 = 9/7
In mixed form: 12/7
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