Add 70/84 and 90/21
1st number: 70/84, 2nd number: 4 6/21
70/84 + 90/21 is 215/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
70/84 = 70 × 1/84 × 1 = 70/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
90/21 = 90 × 4/21 × 4 = 360/84 - Add the two like fractions:
70/84 + 360/84 = 70 + 360/84 = 430/84 - 430/84 simplified gives 215/42
- So, 70/84 + 90/21 = 215/42
In mixed form: 55/42
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