Add 70/84 and 75/20
1st number: 70/84, 2nd number: 3 15/20
70/84 + 75/20 is 55/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
70/84 = 70 × 5/84 × 5 = 350/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
75/20 = 75 × 21/20 × 21 = 1575/420 - Add the two like fractions:
350/420 + 1575/420 = 350 + 1575/420 = 1925/420 - 1925/420 simplified gives 55/12
- So, 70/84 + 75/20 = 55/12
In mixed form: 47/12
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