Add 18/21 and 25/30
18/21 + 25/30 is 71/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
18/21 = 18 × 10/21 × 10 = 180/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
25/30 = 25 × 7/30 × 7 = 175/210 - Add the two like fractions:
180/210 + 175/210 = 180 + 175/210 = 355/210 - 355/210 simplified gives 71/42
- So, 18/21 + 25/30 = 71/42
In mixed form: 129/42
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