Add 7/28 and 84/21
1st number: 7/28, 2nd number: 4 0/21
7/28 + 84/21 is 17/4.
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,
7/28 = 7 × 3/28 × 3 = 21/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
84/21 = 84 × 4/21 × 4 = 336/84 - Add the two like fractions:
21/84 + 336/84 = 21 + 336/84 = 357/84 - 357/84 simplified gives 17/4
- So, 7/28 + 84/21 = 17/4
In mixed form: 41/4
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