Add 30/21 and 40/12
1st number: 1 9/21, 2nd number: 3 4/12
30/21 + 40/12 is 100/21.
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,
30/21 = 30 × 4/21 × 4 = 120/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
40/12 = 40 × 7/12 × 7 = 280/84 - Add the two like fractions:
120/84 + 280/84 = 120 + 280/84 = 400/84 - 400/84 simplified gives 100/21
- So, 30/21 + 40/12 = 100/21
In mixed form: 416/21
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