Add 21/72 and 18/20
21/72 + 18/20 is 143/120.
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,
21/72 = 21 × 5/72 × 5 = 105/360 - Likewise, for the 2nd fraction, since 20 × 18 = 360,
18/20 = 18 × 18/20 × 18 = 324/360 - Add the two like fractions:
105/360 + 324/360 = 105 + 324/360 = 429/360 - 429/360 simplified gives 143/120
- So, 21/72 + 18/20 = 143/120
In mixed form: 123/120
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