Add 28/21 and 42/80
1st number: 1 7/21, 2nd number: 42/80
28/21 + 42/80 is 223/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
28/21 = 28 × 80/21 × 80 = 2240/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
42/80 = 42 × 21/80 × 21 = 882/1680 - Add the two like fractions:
2240/1680 + 882/1680 = 2240 + 882/1680 = 3122/1680 - 3122/1680 simplified gives 223/120
- So, 28/21 + 42/80 = 223/120
In mixed form: 1103/120
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