Add 21/30 and 45/72
21/30 + 45/72 is 53/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 30 × 12 = 360,
21/30 = 21 × 12/30 × 12 = 252/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
45/72 = 45 × 5/72 × 5 = 225/360 - Add the two like fractions:
252/360 + 225/360 = 252 + 225/360 = 477/360 - 477/360 simplified gives 53/40
- So, 21/30 + 45/72 = 53/40
In mixed form: 113/40
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