Add 63/42 and 81/45, Solve 1 21/42 + 1 36/45 as a fraction

Add 63/42 and 81/45

1^st number: 1 21/42, 2^nd number: 1 36/45

63/42 + 81/45 is 33/10.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 42 × 15 = 630,
63/42 = 63 × 15/42 × 15 = 945/630
Likewise, for the 2nd fraction, since 45 × 14 = 630,
81/45 = 81 × 14/45 × 14 = 1134/630
Add the two like fractions:
945/630 + 1134/630 = 945 + 1134/630 = 2079/630
2079/630 simplified gives 33/10
So, 63/42 + 81/45 = 33/10
In mixed form: 33/10

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