Add 84/18 and 21/40
1st number: 4 12/18, 2nd number: 21/40
84/18 + 21/40 is 623/120.
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,
84/18 = 84 × 20/18 × 20 = 1680/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Add the two like fractions:
1680/360 + 189/360 = 1680 + 189/360 = 1869/360 - 1869/360 simplified gives 623/120
- So, 84/18 + 21/40 = 623/120
In mixed form: 523/120
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