Add 42/21 and 9/8, Solve 2 0/21 + 1 1/8 as a fraction

Add 42/21 and 9/8

1^st number: 2 0/21, 2^nd number: 1 1/8

42/21 + 9/8 is 25/8.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
42/21 = 42 × 8/21 × 8 = 336/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
9/8 = 9 × 21/8 × 21 = 189/168
Add the two like fractions:
336/168 + 189/168 = 336 + 189/168 = 525/168
525/168 simplified gives 25/8
So, 42/21 + 9/8 = 25/8
In mixed form: 31/8

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