Add 21/30 and 54/42
1st number: 21/30, 2nd number: 1 12/42
21/30 + 54/42 is 139/70.
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,
54/42 = 54 × 5/42 × 5 = 270/210 - Add the two like fractions:
147/210 + 270/210 = 147 + 270/210 = 417/210 - 417/210 simplified gives 139/70
- So, 21/30 + 54/42 = 139/70
In mixed form: 169/70
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