Add 21/40 and 42/30
1st number: 21/40, 2nd number: 1 12/30
21/40 + 42/30 is 77/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 30 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Likewise, for the 2nd fraction, since 30 × 4 = 120,
42/30 = 42 × 4/30 × 4 = 168/120 - Add the two like fractions:
63/120 + 168/120 = 63 + 168/120 = 231/120 - 231/120 simplified gives 77/40
- So, 21/40 + 42/30 = 77/40
In mixed form: 137/40
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