Add 12/18 and 21/40
12/18 + 21/40 is 143/120.
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,
12/18 = 12 × 20/18 × 20 = 240/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Add the two like fractions:
240/360 + 189/360 = 240 + 189/360 = 429/360 - 429/360 simplified gives 143/120
- So, 12/18 + 21/40 = 143/120
In mixed form: 123/120
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