Add 42/28 and 45/12, Solve 1 14/28 + 3 9/12 as a fraction

Add 42/28 and 45/12

1^st number: 1 14/28, 2^nd number: 3 9/12

42/28 + 45/12 is 21/4.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 28 × 3 = 84,
42/28 = 42 × 3/28 × 3 = 126/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
45/12 = 45 × 7/12 × 7 = 315/84
Add the two like fractions:
126/84 + 315/84 = 126 + 315/84 = 441/84
441/84 simplified gives 21/4
So, 42/28 + 45/12 = 21/4
In mixed form: 51/4

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