Add 15/4 and 30/21
1st number: 3 3/4, 2nd number: 1 9/21
15/4 + 30/21 is 145/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
15/4 = 15 × 21/4 × 21 = 315/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
30/21 = 30 × 4/21 × 4 = 120/84 - Add the two like fractions:
315/84 + 120/84 = 315 + 120/84 = 435/84 - 435/84 simplified gives 145/28
- So, 15/4 + 30/21 = 145/28
In mixed form: 55/28
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