Add 18/21 and 7/15
18/21 + 7/15 is 139/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
18/21 = 18 × 5/21 × 5 = 90/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
7/15 = 7 × 7/15 × 7 = 49/105 - Add the two like fractions:
90/105 + 49/105 = 90 + 49/105 = 139/105 - So, 18/21 + 7/15 = 139/105
In mixed form: 134/105
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