Add 21/80 and 42/18
1st number: 21/80, 2nd number: 2 6/18
21/80 + 42/18 is 623/240.
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,
21/80 = 21 × 9/80 × 9 = 189/720 - Likewise, for the 2nd fraction, since 18 × 40 = 720,
42/18 = 42 × 40/18 × 40 = 1680/720 - Add the two like fractions:
189/720 + 1680/720 = 189 + 1680/720 = 1869/720 - 1869/720 simplified gives 623/240
- So, 21/80 + 42/18 = 623/240
In mixed form: 2143/240
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