Add 3/15 and 42/21
1st number: 3/15, 2nd number: 2 0/21
3/15 + 42/21 is 11/5.
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,
3/15 = 3 × 7/15 × 7 = 21/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
42/21 = 42 × 5/21 × 5 = 210/105 - Add the two like fractions:
21/105 + 210/105 = 21 + 210/105 = 231/105 - 231/105 simplified gives 11/5
- So, 3/15 + 42/21 = 11/5
In mixed form: 21/5
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