Add 21/30 and 5/4
1st number: 21/30, 2nd number: 1 1/4
21/30 + 5/4 is 39/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 4 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 30 × 2 = 60,
21/30 = 21 × 2/30 × 2 = 42/60 - Likewise, for the 2nd fraction, since 4 × 15 = 60,
5/4 = 5 × 15/4 × 15 = 75/60 - Add the two like fractions:
42/60 + 75/60 = 42 + 75/60 = 117/60 - 117/60 simplified gives 39/20
- So, 21/30 + 5/4 = 39/20
In mixed form: 119/20
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