Add 63/42 and 1/90, Solve 1 21/42 + 1/90 as a fraction

Add 63/42 and 1/90

1^st number: 1 21/42, 2^nd number: 1/90

63/42 + 1/90 is 68/45.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 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 90 × 7 = 630,
1/90 = 1 × 7/90 × 7 = 7/630
Add the two like fractions:
945/630 + 7/630 = 945 + 7/630 = 952/630
952/630 simplified gives 68/45
So, 63/42 + 1/90 = 68/45
In mixed form: 123/45

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