Add 42/21 and 7/4, Solve 2 0/21 + 1 3/4 as a fraction

Add 42/21 and 7/4

1^st number: 2 0/21, 2^nd number: 1 3/4

42/21 + 7/4 is 15/4.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 4 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
42/21 = 42 × 4/21 × 4 = 168/84
Likewise, for the 2nd fraction, since 4 × 21 = 84,
7/4 = 7 × 21/4 × 21 = 147/84
Add the two like fractions:
168/84 + 147/84 = 168 + 147/84 = 315/84
315/84 simplified gives 15/4
So, 42/21 + 7/4 = 15/4
In mixed form: 33/4

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