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