Add 72/20 and 98/21, Solve 3 12/20 + 4 14/21 as a fraction

Add 72/20 and 98/21

1^st number: 3 12/20, 2^nd number: 4 14/21

72/20 + 98/21 is 124/15.

Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 20 × 21 = 420,
72/20 = 72 × 21/20 × 21 = 1512/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
98/21 = 98 × 20/21 × 20 = 1960/420
Add the two like fractions:
1512/420 + 1960/420 = 1512 + 1960/420 = 3472/420
3472/420 simplified gives 124/15
So, 72/20 + 98/21 = 124/15
In mixed form: 84/15

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