Add 72/20 and 15/21
1st number: 3 12/20, 2nd number: 15/21
72/20 + 15/21 is 151/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
15/21 = 15 × 20/21 × 20 = 300/420 - Add the two like fractions:
1512/420 + 300/420 = 1512 + 300/420 = 1812/420 - 1812/420 simplified gives 151/35
- So, 72/20 + 15/21 = 151/35
In mixed form: 411/35
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