Add 25/20 and 63/21, Solve 1 5/20 + 3 0/21 as a fraction

Add 25/20 and 63/21

1^st number: 1 5/20, 2^nd number: 3 0/21

25/20 + 63/21 is 17/4.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
25/20 = 25 × 21/20 × 21 = 525/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
63/21 = 63 × 20/21 × 20 = 1260/420
Add the two like fractions:
525/420 + 1260/420 = 525 + 1260/420 = 1785/420
1785/420 simplified gives 17/4
So, 25/20 + 63/21 = 17/4
In mixed form: 41/4

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