Add 42/21 and 7/28, Solve 2 0/21 + 7/28 as a fraction

Add 42/21 and 7/28

1^st number: 2 0/21, 2^nd number: 7/28

42/21 + 7/28 is 9/4.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 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 28 × 3 = 84,
7/28 = 7 × 3/28 × 3 = 21/84
Add the two like fractions:
168/84 + 21/84 = 168 + 21/84 = 189/84
189/84 simplified gives 9/4
So, 42/21 + 7/28 = 9/4
In mixed form: 21/4

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