Add 9/8 and 63/42, Solve 1 1/8 + 1 21/42 as a fraction

Add 9/8 and 63/42

1^st number: 1 1/8, 2^nd number: 1 21/42

9/8 + 63/42 is 21/8.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 42 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
9/8 = 9 × 21/8 × 21 = 189/168
Likewise, for the 2nd fraction, since 42 × 4 = 168,
63/42 = 63 × 4/42 × 4 = 252/168
Add the two like fractions:
189/168 + 252/168 = 189 + 252/168 = 441/168
441/168 simplified gives 21/8
So, 9/8 + 63/42 = 21/8
In mixed form: 25/8

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