Add 63/84 and 90/20, Solve 63/84 + 4 10/20 as a fraction

Add 63/84 and 90/20

1^st number: 63/84, 2^nd number: 4 10/20

63/84 + 90/20 is 21/4.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
63/84 = 63 × 5/84 × 5 = 315/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
90/20 = 90 × 21/20 × 21 = 1890/420
Add the two like fractions:
315/420 + 1890/420 = 315 + 1890/420 = 2205/420
2205/420 simplified gives 21/4
So, 63/84 + 90/20 = 21/4
In mixed form: 51/4

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