Add 21/40 and 30/18
1st number: 21/40, 2nd number: 1 12/18
21/40 + 30/18 is 263/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 18 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Likewise, for the 2nd fraction, since 18 × 20 = 360,
30/18 = 30 × 20/18 × 20 = 600/360 - Add the two like fractions:
189/360 + 600/360 = 189 + 600/360 = 789/360 - 789/360 simplified gives 263/120
- So, 21/40 + 30/18 = 263/120
In mixed form: 223/120
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