Add 21/80 and 42/45
21/80 + 42/45 is 287/240.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 45 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 45 × 16 = 720,
42/45 = 42 × 16/45 × 16 = 672/720 - Add the two like fractions:
189/720 + 672/720 = 189 + 672/720 = 861/720 - 861/720 simplified gives 287/240
- So, 21/80 + 42/45 = 287/240
In mixed form: 147/240
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