Add 21/4 and 20/30
1st number: 5 1/4, 2nd number: 20/30
21/4 + 20/30 is 71/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 30 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 4 × 15 = 60,
21/4 = 21 × 15/4 × 15 = 315/60 - Likewise, for the 2nd fraction, since 30 × 2 = 60,
20/30 = 20 × 2/30 × 2 = 40/60 - Add the two like fractions:
315/60 + 40/60 = 315 + 40/60 = 355/60 - 355/60 simplified gives 71/12
- So, 21/4 + 20/30 = 71/12
In mixed form: 511/12
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