Add 15/35 and 80/21
1st number: 15/35, 2nd number: 3 17/21
15/35 + 80/21 is 89/21.
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,
80/21 = 80 × 5/21 × 5 = 400/105 - Add the two like fractions:
45/105 + 400/105 = 45 + 400/105 = 445/105 - 445/105 simplified gives 89/21
- So, 15/35 + 80/21 = 89/21
In mixed form: 45/21
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