Add 21/15 and 75/30
1st number: 1 6/15, 2nd number: 2 15/30
21/15 + 75/30 is 39/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 30 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 15 × 2 = 30,
21/15 = 21 × 2/15 × 2 = 42/30 - Likewise, for the 2nd fraction, since 30 × 1 = 30,
75/30 = 75 × 1/30 × 1 = 75/30 - Add the two like fractions:
42/30 + 75/30 = 42 + 75/30 = 117/30 - 117/30 simplified gives 39/10
- So, 21/15 + 75/30 = 39/10
In mixed form: 39/10
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