Add 21/72 and 20/45
21/72 + 20/45 is 53/72.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 45 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 45 × 8 = 360,
20/45 = 20 × 8/45 × 8 = 160/360 - Add the two like fractions:
105/360 + 160/360 = 105 + 160/360 = 265/360 - 265/360 simplified gives 53/72
- So, 21/72 + 20/45 = 53/72
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