Add 72/21 and 20/35
1st number: 3 9/21, 2nd number: 20/35
72/21 + 20/35 is 4/1.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 35 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
72/21 = 72 × 5/21 × 5 = 360/105 - Likewise, for the 2nd fraction, since 35 × 3 = 105,
20/35 = 20 × 3/35 × 3 = 60/105 - Add the two like fractions:
360/105 + 60/105 = 360 + 60/105 = 420/105 - 420/105 simplified gives 4/1
- So, 72/21 + 20/35 = 4/1
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