Add 28/15 and 4/21
1st number: 1 13/15, 2nd number: 4/21
28/15 + 4/21 is 72/35.
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,
28/15 = 28 × 7/15 × 7 = 196/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
4/21 = 4 × 5/21 × 5 = 20/105 - Add the two like fractions:
196/105 + 20/105 = 196 + 20/105 = 216/105 - 216/105 simplified gives 72/35
- So, 28/15 + 4/21 = 72/35
In mixed form: 22/35
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