Add 18/80 and 45/21
1st number: 18/80, 2nd number: 2 3/21
18/80 + 45/21 is 663/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
18/80 = 18 × 21/80 × 21 = 378/1680 - Likewise, for the 2nd fraction, since 21 × 80 = 1680,
45/21 = 45 × 80/21 × 80 = 3600/1680 - Add the two like fractions:
378/1680 + 3600/1680 = 378 + 3600/1680 = 3978/1680 - 3978/1680 simplified gives 663/280
- So, 18/80 + 45/21 = 663/280
In mixed form: 2103/280
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