Add 28/40 and 98/21, Solve 28/40 + 4 14/21 as a fraction

Add 28/40 and 98/21

1^st number: 28/40, 2^nd number: 4 14/21

28/40 + 98/21 is 161/30.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
28/40 = 28 × 21/40 × 21 = 588/840
Likewise, for the 2nd fraction, since 21 × 40 = 840,
98/21 = 98 × 40/21 × 40 = 3920/840
Add the two like fractions:
588/840 + 3920/840 = 588 + 3920/840 = 4508/840
4508/840 simplified gives 161/30
So, 28/40 + 98/21 = 161/30
In mixed form: 511/30

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