Add 54/70 and 70/21
1st number: 54/70, 2nd number: 3 7/21
54/70 + 70/21 is 431/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
54/70 = 54 × 3/70 × 3 = 162/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
70/21 = 70 × 10/21 × 10 = 700/210 - Add the two like fractions:
162/210 + 700/210 = 162 + 700/210 = 862/210 - 862/210 simplified gives 431/105
- So, 54/70 + 70/21 = 431/105
In mixed form: 411/105
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