Add 28/21 and 98/12, Solve 1 7/21 + 8 2/12 as a fraction

Add 28/21 and 98/12

1^st number: 1 7/21, 2^nd number: 8 2/12

28/21 + 98/12 is 19/2.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 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 12 × 7 = 84,
98/12 = 98 × 7/12 × 7 = 686/84
Add the two like fractions:
112/84 + 686/84 = 112 + 686/84 = 798/84
798/84 simplified gives 19/2
So, 28/21 + 98/12 = 19/2
In mixed form: 91/2

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