Add 21/15 and 18/21
1st number: 1 6/15, 2nd number: 18/21
21/15 + 18/21 is 79/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
21/15 = 21 × 7/15 × 7 = 147/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
18/21 = 18 × 5/21 × 5 = 90/105 - Add the two like fractions:
147/105 + 90/105 = 147 + 90/105 = 237/105 - 237/105 simplified gives 79/35
- So, 21/15 + 18/21 = 79/35
In mixed form: 29/35
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