Add 21/42 and 45/25, Solve 21/42 + 1 20/25 as a fraction

Add 21/42 and 45/25

1^st number: 21/42, 2^nd number: 1 20/25

21/42 + 45/25 is 23/10.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 25 is 1050

Next, find the equivalent fraction of both fractional numbers with denominator 1050
For the 1st fraction, since 42 × 25 = 1050,
21/42 = 21 × 25/42 × 25 = 525/1050
Likewise, for the 2nd fraction, since 25 × 42 = 1050,
45/25 = 45 × 42/25 × 42 = 1890/1050
Add the two like fractions:
525/1050 + 1890/1050 = 525 + 1890/1050 = 2415/1050
2415/1050 simplified gives 23/10
So, 21/42 + 45/25 = 23/10
In mixed form: 23/10

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