Add 70/20 and 81/84
1st number: 3 10/20, 2nd number: 81/84
70/20 + 81/84 is 125/28.
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,
70/20 = 70 × 21/20 × 21 = 1470/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
81/84 = 81 × 5/84 × 5 = 405/420 - Add the two like fractions:
1470/420 + 405/420 = 1470 + 405/420 = 1875/420 - 1875/420 simplified gives 125/28
- So, 70/20 + 81/84 = 125/28
In mixed form: 413/28
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