Add 63/42 and 7/81, Solve 1 21/42 + 7/81 as a fraction

Add 63/42 and 7/81

1^st number: 1 21/42, 2^nd number: 7/81

63/42 + 7/81 is 257/162.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 81 is 1134

Next, find the equivalent fraction of both fractional numbers with denominator 1134
For the 1st fraction, since 42 × 27 = 1134,
63/42 = 63 × 27/42 × 27 = 1701/1134
Likewise, for the 2nd fraction, since 81 × 14 = 1134,
7/81 = 7 × 14/81 × 14 = 98/1134
Add the two like fractions:
1701/1134 + 98/1134 = 1701 + 98/1134 = 1799/1134
1799/1134 simplified gives 257/162
So, 63/42 + 7/81 = 257/162
In mixed form: 195/162

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