Add 21/8 and 42/30
1st number: 2 5/8, 2nd number: 1 12/30
21/8 + 42/30 is 161/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 30 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 8 × 15 = 120,
21/8 = 21 × 15/8 × 15 = 315/120 - Likewise, for the 2nd fraction, since 30 × 4 = 120,
42/30 = 42 × 4/30 × 4 = 168/120 - Add the two like fractions:
315/120 + 168/120 = 315 + 168/120 = 483/120 - 483/120 simplified gives 161/40
- So, 21/8 + 42/30 = 161/40
In mixed form: 41/40
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