Add 63/42 and 90/28, Solve 1 21/42 + 3 6/28 as a fraction

Add 63/42 and 90/28

1^st number: 1 21/42, 2^nd number: 3 6/28

63/42 + 90/28 is 33/7.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 28 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 42 × 2 = 84,
63/42 = 63 × 2/42 × 2 = 126/84
Likewise, for the 2nd fraction, since 28 × 3 = 84,
90/28 = 90 × 3/28 × 3 = 270/84
Add the two like fractions:
126/84 + 270/84 = 126 + 270/84 = 396/84
396/84 simplified gives 33/7
So, 63/42 + 90/28 = 33/7
In mixed form: 45/7

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