Add 10/12 and 18/21
10/12 + 18/21 is 71/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
10/12 = 10 × 7/12 × 7 = 70/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
18/21 = 18 × 4/21 × 4 = 72/84 - Add the two like fractions:
70/84 + 72/84 = 70 + 72/84 = 142/84 - 142/84 simplified gives 71/42
- So, 10/12 + 18/21 = 71/42
In mixed form: 129/42
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