Add 30/21 and 40/28
1st number: 1 9/21, 2nd number: 1 12/28
30/21 + 40/28 is 20/7.
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,
30/21 = 30 × 4/21 × 4 = 120/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
40/28 = 40 × 3/28 × 3 = 120/84 - Add the two like fractions:
120/84 + 120/84 = 120 + 120/84 = 240/84 - 240/84 simplified gives 20/7
- So, 30/21 + 40/28 = 20/7
In mixed form: 26/7
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