Add 72/18 and 21/45
1st number: 4 0/18, 2nd number: 21/45
72/18 + 21/45 is 67/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 45 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 18 × 5 = 90,
72/18 = 72 × 5/18 × 5 = 360/90 - Likewise, for the 2nd fraction, since 45 × 2 = 90,
21/45 = 21 × 2/45 × 2 = 42/90 - Add the two like fractions:
360/90 + 42/90 = 360 + 42/90 = 402/90 - 402/90 simplified gives 67/15
- So, 72/18 + 21/45 = 67/15
In mixed form: 47/15
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