Add 21/12 and 84/80
1st number: 1 9/12, 2nd number: 1 4/80
21/12 + 84/80 is 14/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 80 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 12 × 20 = 240,
21/12 = 21 × 20/12 × 20 = 420/240 - Likewise, for the 2nd fraction, since 80 × 3 = 240,
84/80 = 84 × 3/80 × 3 = 252/240 - Add the two like fractions:
420/240 + 252/240 = 420 + 252/240 = 672/240 - 672/240 simplified gives 14/5
- So, 21/12 + 84/80 = 14/5
In mixed form: 24/5
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