Add 21/10 and 63/8
1st number: 2 1/10, 2nd number: 7 7/8
21/10 + 63/8 is 399/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 8 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 10 × 4 = 40,
21/10 = 21 × 4/10 × 4 = 84/40 - Likewise, for the 2nd fraction, since 8 × 5 = 40,
63/8 = 63 × 5/8 × 5 = 315/40 - Add the two like fractions:
84/40 + 315/40 = 84 + 315/40 = 399/40 - So, 21/10 + 63/8 = 399/40
In mixed form: 939/40
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