Add 28/21 and 30/28, Solve 1 7/21 + 1 2/28 as a fraction

Add 28/21 and 30/28

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

28/21 + 30/28 is 101/42.

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,
28/21 = 28 × 4/21 × 4 = 112/84
Likewise, for the 2nd fraction, since 28 × 3 = 84,
30/28 = 30 × 3/28 × 3 = 90/84
Add the two like fractions:
112/84 + 90/84 = 112 + 90/84 = 202/84
202/84 simplified gives 101/42
So, 28/21 + 30/28 = 101/42
In mixed form: 217/42

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