Add 21/42 and 63/45, Solve 21/42 + 1 18/45 as a fraction

Add 21/42 and 63/45

1^st number: 21/42, 2^nd number: 1 18/45

21/42 + 63/45 is 19/10.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 42 × 15 = 630,
21/42 = 21 × 15/42 × 15 = 315/630
Likewise, for the 2nd fraction, since 45 × 14 = 630,
63/45 = 63 × 14/45 × 14 = 882/630
Add the two like fractions:
315/630 + 882/630 = 315 + 882/630 = 1197/630
1197/630 simplified gives 19/10
So, 21/42 + 63/45 = 19/10
In mixed form: 19/10

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