Add 3/21 and 15/7
1st number: 3/21, 2nd number: 2 1/7
3/21 + 15/7 is 16/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
3/21 = 3 × 1/21 × 1 = 3/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
15/7 = 15 × 3/7 × 3 = 45/21 - Add the two like fractions:
3/21 + 45/21 = 3 + 45/21 = 48/21 - 48/21 simplified gives 16/7
- So, 3/21 + 15/7 = 16/7
In mixed form: 22/7
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