Add 72/84 and 42/15
1st number: 72/84, 2nd number: 2 12/15
72/84 + 42/15 is 128/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 15 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 15 × 28 = 420,
42/15 = 42 × 28/15 × 28 = 1176/420 - Add the two like fractions:
360/420 + 1176/420 = 360 + 1176/420 = 1536/420 - 1536/420 simplified gives 128/35
- So, 72/84 + 42/15 = 128/35
In mixed form: 323/35
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