Add 21/30 and 25/42
21/30 + 25/42 is 136/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
25/42 = 25 × 5/42 × 5 = 125/210 - Add the two like fractions:
147/210 + 125/210 = 147 + 125/210 = 272/210 - 272/210 simplified gives 136/105
- So, 21/30 + 25/42 = 136/105
In mixed form: 131/105
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