Add 90/20 and 81/84
1st number: 4 10/20, 2nd number: 81/84
90/20 + 81/84 is 153/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
90/20 = 90 × 21/20 × 21 = 1890/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
81/84 = 81 × 5/84 × 5 = 405/420 - Add the two like fractions:
1890/420 + 405/420 = 1890 + 405/420 = 2295/420 - 2295/420 simplified gives 153/28
- So, 90/20 + 81/84 = 153/28
In mixed form: 513/28
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