Add 81/84 and 90/70
1st number: 81/84, 2nd number: 1 20/70
81/84 + 90/70 is 9/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
81/84 = 81 × 5/84 × 5 = 405/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
90/70 = 90 × 6/70 × 6 = 540/420 - Add the two like fractions:
405/420 + 540/420 = 405 + 540/420 = 945/420 - 945/420 simplified gives 9/4
- So, 81/84 + 90/70 = 9/4
In mixed form: 21/4
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