Add 21/15 and 28/72
1st number: 1 6/15, 2nd number: 28/72
21/15 + 28/72 is 161/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 15 × 24 = 360,
21/15 = 21 × 24/15 × 24 = 504/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
28/72 = 28 × 5/72 × 5 = 140/360 - Add the two like fractions:
504/360 + 140/360 = 504 + 140/360 = 644/360 - 644/360 simplified gives 161/90
- So, 21/15 + 28/72 = 161/90
In mixed form: 171/90
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