Add 18/21 and 15/40
18/21 + 15/40 is 69/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
18/21 = 18 × 40/21 × 40 = 720/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
15/40 = 15 × 21/40 × 21 = 315/840 - Add the two like fractions:
720/840 + 315/840 = 720 + 315/840 = 1035/840 - 1035/840 simplified gives 69/56
- So, 18/21 + 15/40 = 69/56
In mixed form: 113/56
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