Add 21/15 and 63/8
1st number: 1 6/15, 2nd number: 7 7/8
21/15 + 63/8 is 371/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 8 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 15 × 8 = 120,
21/15 = 21 × 8/15 × 8 = 168/120 - Likewise, for the 2nd fraction, since 8 × 15 = 120,
63/8 = 63 × 15/8 × 15 = 945/120 - Add the two like fractions:
168/120 + 945/120 = 168 + 945/120 = 1113/120 - 1113/120 simplified gives 371/40
- So, 21/15 + 63/8 = 371/40
In mixed form: 911/40
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