Add 72/60 and 42/21
1st number: 1 12/60, 2nd number: 2 0/21
72/60 + 42/21 is 16/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 60 × 7 = 420,
72/60 = 72 × 7/60 × 7 = 504/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
42/21 = 42 × 20/21 × 20 = 840/420 - Add the two like fractions:
504/420 + 840/420 = 504 + 840/420 = 1344/420 - 1344/420 simplified gives 16/5
- So, 72/60 + 42/21 = 16/5
In mixed form: 31/5
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