Add 15/21 and 18/40
15/21 + 18/40 is 163/140.
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,
15/21 = 15 × 40/21 × 40 = 600/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
18/40 = 18 × 21/40 × 21 = 378/840 - Add the two like fractions:
600/840 + 378/840 = 600 + 378/840 = 978/840 - 978/840 simplified gives 163/140
- So, 15/21 + 18/40 = 163/140
In mixed form: 123/140
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