Add 15/35 and 5/21
15/35 + 5/21 is 2/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 35 × 3 = 105,
15/35 = 15 × 3/35 × 3 = 45/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
5/21 = 5 × 5/21 × 5 = 25/105 - Add the two like fractions:
45/105 + 25/105 = 45 + 25/105 = 70/105 - 70/105 simplified gives 2/3
- So, 15/35 + 5/21 = 2/3
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