Add 90/21 and 21/28
1st number: 4 6/21, 2nd number: 21/28
90/21 + 21/28 is 141/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 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 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84 - Add the two like fractions:
360/84 + 63/84 = 360 + 63/84 = 423/84 - 423/84 simplified gives 141/28
- So, 90/21 + 21/28 = 141/28
In mixed form: 51/28
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