Add 4/5 and 7/21
4/5 + 7/21 is 17/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
4/5 = 4 × 21/5 × 21 = 84/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
7/21 = 7 × 5/21 × 5 = 35/105 - Add the two like fractions:
84/105 + 35/105 = 84 + 35/105 = 119/105 - 119/105 simplified gives 17/15
- So, 4/5 + 7/21 = 17/15
In mixed form: 12/15
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