Add 72/84 and 21/30
72/84 + 21/30 is 109/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 30 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 30 × 14 = 420,
21/30 = 21 × 14/30 × 14 = 294/420 - Add the two like fractions:
360/420 + 294/420 = 360 + 294/420 = 654/420 - 654/420 simplified gives 109/70
- So, 72/84 + 21/30 = 109/70
In mixed form: 139/70
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