Add 70/12 and 90/21
1st number: 5 10/12, 2nd number: 4 6/21
70/12 + 90/21 is 425/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
70/12 = 70 × 7/12 × 7 = 490/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
90/21 = 90 × 4/21 × 4 = 360/84 - Add the two like fractions:
490/84 + 360/84 = 490 + 360/84 = 850/84 - 850/84 simplified gives 425/42
- So, 70/12 + 90/21 = 425/42
In mixed form: 105/42
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