Add 15/21 and 7/20
15/21 + 7/20 is 149/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
15/21 = 15 × 20/21 × 20 = 300/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
7/20 = 7 × 21/20 × 21 = 147/420 - Add the two like fractions:
300/420 + 147/420 = 300 + 147/420 = 447/420 - 447/420 simplified gives 149/140
- So, 15/21 + 7/20 = 149/140
In mixed form: 19/140
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