Add 72/21 and 45/60
1st number: 3 9/21, 2nd number: 45/60
72/21 + 45/60 is 117/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 60 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 60 × 7 = 420,
45/60 = 45 × 7/60 × 7 = 315/420 - Add the two like fractions:
1440/420 + 315/420 = 1440 + 315/420 = 1755/420 - 1755/420 simplified gives 117/28
- So, 72/21 + 45/60 = 117/28
In mixed form: 45/28
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