Add 72/21 and 42/20
1st number: 3 9/21, 2nd number: 2 2/20
72/21 + 42/20 is 387/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
72/21 = 72 × 20/21 × 20 = 1440/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
42/20 = 42 × 21/20 × 21 = 882/420 - Add the two like fractions:
1440/420 + 882/420 = 1440 + 882/420 = 2322/420 - 2322/420 simplified gives 387/70
- So, 72/21 + 42/20 = 387/70
In mixed form: 537/70
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