Add 21/80 and 42/40
1st number: 21/80, 2nd number: 1 2/40
21/80 + 42/40 is 21/16.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 40 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
21/80 = 21 × 1/80 × 1 = 21/80 - Likewise, for the 2nd fraction, since 40 × 2 = 80,
42/40 = 42 × 2/40 × 2 = 84/80 - Add the two like fractions:
21/80 + 84/80 = 21 + 84/80 = 105/80 - 105/80 simplified gives 21/16
- So, 21/80 + 42/40 = 21/16
In mixed form: 15/16
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