Add 42/80 and 21/18
1st number: 42/80, 2nd number: 1 3/18
42/80 + 21/18 is 203/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 18 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
42/80 = 42 × 9/80 × 9 = 378/720 - Likewise, for the 2nd fraction, since 18 × 40 = 720,
21/18 = 21 × 40/18 × 40 = 840/720 - Add the two like fractions:
378/720 + 840/720 = 378 + 840/720 = 1218/720 - 1218/720 simplified gives 203/120
- So, 42/80 + 21/18 = 203/120
In mixed form: 183/120
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