Add 40/45 and 63/42, Solve 40/45 + 1 21/42 as a fraction

Add 40/45 and 63/42

1^st number: 40/45, 2^nd number: 1 21/42

40/45 + 63/42 is 43/18.

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

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 45 × 14 = 630,
40/45 = 40 × 14/45 × 14 = 560/630
Likewise, for the 2nd fraction, since 42 × 15 = 630,
63/42 = 63 × 15/42 × 15 = 945/630
Add the two like fractions:
560/630 + 945/630 = 560 + 945/630 = 1505/630
1505/630 simplified gives 43/18
So, 40/45 + 63/42 = 43/18
In mixed form: 27/18

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