Add 63/42 and 75/20, Solve 1 21/42 + 3 15/20 as a fraction

Add 63/42 and 75/20

1^st number: 1 21/42, 2^nd number: 3 15/20

63/42 + 75/20 is 21/4.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 42 × 10 = 420,
63/42 = 63 × 10/42 × 10 = 630/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
75/20 = 75 × 21/20 × 21 = 1575/420
Add the two like fractions:
630/420 + 1575/420 = 630 + 1575/420 = 2205/420
2205/420 simplified gives 21/4
So, 63/42 + 75/20 = 21/4
In mixed form: 51/4

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