Add 21/20 and 40/72
1st number: 1 1/20, 2nd number: 40/72
21/20 + 40/72 is 289/180.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 20 × 18 = 360,
21/20 = 21 × 18/20 × 18 = 378/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
40/72 = 40 × 5/72 × 5 = 200/360 - Add the two like fractions:
378/360 + 200/360 = 378 + 200/360 = 578/360 - 578/360 simplified gives 289/180
- So, 21/20 + 40/72 = 289/180
In mixed form: 1109/180
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