Add 21/45 and 45/72
21/45 + 45/72 is 131/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
21/45 = 21 × 8/45 × 8 = 168/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
45/72 = 45 × 5/72 × 5 = 225/360 - Add the two like fractions:
168/360 + 225/360 = 168 + 225/360 = 393/360 - 393/360 simplified gives 131/120
- So, 21/45 + 45/72 = 131/120
In mixed form: 111/120
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