Add 21/40 and 42/60
21/40 + 42/60 is 49/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 60 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 60 × 2 = 120,
42/60 = 42 × 2/60 × 2 = 84/120 - Add the two like fractions:
63/120 + 84/120 = 63 + 84/120 = 147/120 - 147/120 simplified gives 49/40
- So, 21/40 + 42/60 = 49/40
In mixed form: 19/40
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