Add 21/30 and 63/8
1st number: 21/30, 2nd number: 7 7/8
21/30 + 63/8 is 343/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 8 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
21/30 = 21 × 4/30 × 4 = 84/120 - Likewise, for the 2nd fraction, since 8 × 15 = 120,
63/8 = 63 × 15/8 × 15 = 945/120 - Add the two like fractions:
84/120 + 945/120 = 84 + 945/120 = 1029/120 - 1029/120 simplified gives 343/40
- So, 21/30 + 63/8 = 343/40
In mixed form: 823/40
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