Add 21/42 and 45/24, Solve 21/42 + 1 21/24 as a fraction

Add 21/42 and 45/24

1^st number: 21/42, 2^nd number: 1 21/24

21/42 + 45/24 is 19/8.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 24 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 42 × 4 = 168,
21/42 = 21 × 4/42 × 4 = 84/168
Likewise, for the 2nd fraction, since 24 × 7 = 168,
45/24 = 45 × 7/24 × 7 = 315/168
Add the two like fractions:
84/168 + 315/168 = 84 + 315/168 = 399/168
399/168 simplified gives 19/8
So, 21/42 + 45/24 = 19/8
In mixed form: 23/8

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