Add 72/18 and 21/40
1st number: 4 0/18, 2nd number: 21/40
72/18 + 21/40 is 181/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 18 × 20 = 360,
72/18 = 72 × 20/18 × 20 = 1440/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Add the two like fractions:
1440/360 + 189/360 = 1440 + 189/360 = 1629/360 - 1629/360 simplified gives 181/40
- So, 72/18 + 21/40 = 181/40
In mixed form: 421/40
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