Add 63/72 and 21/20
1st number: 63/72, 2nd number: 1 1/20
63/72 + 21/20 is 77/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 20 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
63/72 = 63 × 5/72 × 5 = 315/360 - Likewise, for the 2nd fraction, since 20 × 18 = 360,
21/20 = 21 × 18/20 × 18 = 378/360 - Add the two like fractions:
315/360 + 378/360 = 315 + 378/360 = 693/360 - 693/360 simplified gives 77/40
- So, 63/72 + 21/20 = 77/40
In mixed form: 137/40
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