Add 90/28 and 70/21
1st number: 3 6/28, 2nd number: 3 7/21
90/28 + 70/21 is 275/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
90/28 = 90 × 3/28 × 3 = 270/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
70/21 = 70 × 4/21 × 4 = 280/84 - Add the two like fractions:
270/84 + 280/84 = 270 + 280/84 = 550/84 - 550/84 simplified gives 275/42
- So, 90/28 + 70/21 = 275/42
In mixed form: 623/42
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