Add 15/30 and 84/21
1st number: 15/30, 2nd number: 4 0/21
15/30 + 84/21 is 9/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
15/30 = 15 × 7/30 × 7 = 105/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
84/21 = 84 × 10/21 × 10 = 840/210 - Add the two like fractions:
105/210 + 840/210 = 105 + 840/210 = 945/210 - 945/210 simplified gives 9/2
- So, 15/30 + 84/21 = 9/2
In mixed form: 41/2
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