Add 21/20 and 28/40
1st number: 1 1/20, 2nd number: 28/40
21/20 + 28/40 is 7/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 20 × 2 = 40,
21/20 = 21 × 2/20 × 2 = 42/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
28/40 = 28 × 1/40 × 1 = 28/40 - Add the two like fractions:
42/40 + 28/40 = 42 + 28/40 = 70/40 - 70/40 simplified gives 7/4
- So, 21/20 + 28/40 = 7/4
In mixed form: 13/4
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